Diesel ECU Location?

21st February 2010, 01:31

Im thinking of fitting a new set of dials to get rid of that awful clock, and was wondering if its possible to add a tachometer to a 97 1.5 Diesel.

Ive noticed most of the petrol models have the ECU under a silver metal cover, to the left side of the engine. But all mine has is a little black box, is this the ECU on the diesel model, or is this located elsewhere?

21st February 2010, 06:49

The diesel models are mechanical and don't use an ECU.

The black box you're thinking of is the expansion/header tank for the radiator.

21st February 2010, 10:14

Nah mate, i was on about another very small black box to the right side of the expansion tank. Ive put a ring round it in this pic http://i49.tinypic.com/2qrzrdh.jpg (Not my engine, mines in better condition)

Is there anyway a tachometer can be fitted without the ECU? As ive seen some have them.

21st February 2010, 10:25

most old type diesels run the rev counter off the alternator

26th June 2013, 23:56

Hi All, (+ anybody else on here who has the relevant techie info), i have just found your comments about " ECU's " in the Citroen Saxo Diesel - via Google.

I was very interested in the comments & advice given to the original poster in this thread regarding ECU's in diesel saxo's.

I'm currently looking at getting my daughter a Citroen Saxo 1.5 diesel, but like many people was a little weary of getting her a cheap car to learn to drive in, whilst keeping the costs of motoring & maintenance as low as possible.

Ideally i was looking for a lower-tech model i.e; Citroen Saxo 1.5 diesel (or dare i say it on here a Pug 106 1.5d - as its the same engine), preferably a non-ECU model. (to keep things simple).

Can anyone tell me;

- how i can distinguish between models which have an ECU / or no ECU?

- can i tell from looking at the fuel pump, etc?

Apologies for the ECU interrogation, but i would appreciate the benefit of some welcome saxo diesel knowledge to guide me in the right direction

- Also, is there anything else i should be looking out for, or be weary of - when buying a Citroen Saxo 1.5 diesel - mechanical / electrical? (thanks in advance).

Plus i wanted to say, looks like a good forum, enjoying the content & the many subjects covered on here, which i've been browsing through....

27th June 2013, 00:34

Quote:

Originally Posted by vinrouge

Hi All, (+ anybody else on here who has the relevant techie info), i have just found your comments about " ECU's " in the Citroen Saxo Diesel - via Google.

I was very interested in the comments & advice given to the original poster in this thread regarding ECU's in diesel saxo's.

I'm currently looking at getting my daughter a Citroen Saxo 1.5 diesel, but like many people was a little weary of getting her a cheap car to learn to drive in, whilst keeping the costs of motoring & maintenance as low as possible.

Ideally i was looking for a lower-tech model i.e; Citroen Saxo 1.5 diesel (or dare i say it on here a Pug 106 1.5d - as its the same engine), preferably a non-ECU model. (to keep things simple).

Can anyone tell me;

- how i can distinguish between models which have an ECU / or no ECU?

- can i tell from looking at the fuel pump, etc?

Apologies for the ECU interrogation, but i would appreciate the benefit of some welcome saxo diesel knowledge to guide me in the right direction

- Also, is there anything else i should be looking out for, or be weary of - when buying a Citroen Saxo 1.5 diesel - mechanical / electrical? (thanks in advance).

Plus i wanted to say, looks like a good forum, enjoying the content & the many subjects covered on here, which i've been browsing through....

Bad luck because I'm on here as well

Same story on a Saxo, ECU sits on top of the battery if it has one.

As before, rear axle is a must for checking. Any signs of camber on the rear and it'll probably be needing an Axle.

check front ball joints

Make sure it starts smoothly, don't be off if you find one that's a little lumpy though, it's probably just needing a new battery or glow plugs.

Stay away from keypad models.

Stay away from models with a sunroof, unless you like having a wet arse LOL

Indicator switches often go faulty, relay randomly clicks wile driving.

Wiper stalk can go faulty as well, sometimes they'll stop in the middle of the screen etc.

27th June 2013, 00:36

The ecu ones have a visual ecu under the bonnet but i believe no saxo or 106 diesels have them... There all mechanical pump... Also watch out for rust and they do like a head hasket... They are good on fuel but you will be doing a hg on that at some point...

Fyi the 206hdi is bulletproof and there arent really many problems... If the pump goes down on a saxo they arent cheap to replace...

Welcome to the forum btw

27th June 2013, 00:53

Quote:

Originally Posted by greyjasper51

The ecu ones have a visual ecu under the bonnet but i believe no saxo or 106 diesels have them... There all mechanical pump... Also watch out for rust and they do like a head hasket... They are good on fuel but you will be doing a hg on that at some point...

Fyi the 206hdi is bulletproof and there arent really many problems... If the pump goes down on a saxo they arent cheap to replace...

Welcome to the forum btw

2001 models onwards all have ECU's

it controls the EGR valve and the timing advance.

Head gasket issues are mythical. 1.5D has the strongest head gasket setup (3 layers of solid copper). it's only a problem on the older 1.4D with the alloy blocks which warp easily.

I've re-used head gaskets on the 1.5D with no problems, I don't recommend it but I was stuck! lol done 30,000 miles on it so far.

Avoid pump issues by getting a Saxo/106 with a Bosch pump. they are fairly cheap if you get a second hand one. they are fitted to many many different cars and lawnmowers.

27th June 2013, 08:57

Never seen a 2001 on diesel saxo or 106 must be fucking rare!! Must be an electronically advance or retard mechanical pump...

Dads had loads of 1.5d headgaskets in todo over the years... (Not the same one comming back either) We dont bother now its not worth it, same as k series ones we dont bother with anymore there not worth the agro...

Im sure your right with the bosch ones... On the 405 xud lump you cant swap lucas for bosch... Assumed it was the same... But the bosch ones can run on chip oil... (Pre 2001)

27th June 2013, 09:13

if you get pump/ecu issues --just manully adjust timing on the pump pulley till it oges well and no smoke
don,t forget to mark pulley before you start--as the timing adjustment electronics is all that usually goes wrong#
could never work out why they never fitted a wee turbo to them

27th June 2013, 10:21

OP: fitting a rev counter can be done. You can get alternators that have a rev counter output. Or I believe, but have't confirmed, that you can fit a hall effect sensor to the read the flywheel (the way the 1.1 pretols etc did) and get an output that way.

Quote:

Originally Posted by MartinObviously

Bad luck because I'm on here as well

Same story on a Saxo, ECU sits on top of the battery if it has one.

As before, rear axle is a must for checking. Any signs of camber on the rear and it'll probably be needing an Axle.

check front ball joints

Make sure it starts smoothly, don't be off if you find one that's a little lumpy though, it's probably just needing a new battery or glow plugs.

Stay away from keypad models.

Stay away from models with a sunroof, unless you like having a wet arse LOL

Indicator switches often go faulty, relay randomly clicks wile driving.

Wiper stalk can go faulty as well, sometimes they'll stop in the middle of the screen etc.

Yup, me too! lol! As martin has said really, the 1.5D engine will be the least of your worries. Give the rest of the car a through going over before worrying about the engine. Also, the brakes (247x10mm solid disks) on the 1.5D's weren't really up to much as standard, and normally need a hefty shove to stop from speed. A common upgrade is 106GTi brakes which have vented disks, along with a set of half decent pads. Makes a world of difference. I went 1 step further up the ladder and got a 266mm conversion from a 307. Car will now lock both front tires (205/40/17's) at 70mph if required.

Quote:

Originally Posted by axsaxoman

if you get pump/ecu issues --just manully adjust timing on the pump pulley till it oges well and no smoke
don,t forget to mark pulley before you start--as the timing adjustment electronics is all that usually goes wrong#
could never work out why they never fitted a wee turbo to them

The pump timing is all still mechanical. The ecu just runs egr and bits like that.
If they had fitted a turbo the clutch wouldn't be able to hack it. There's a guy over on 106oc who runs a light pressure turbo (7psi or so iirc) on a standard 1.5D (with an XUD9 pump) and he gets epic clutch slip issues if he turns it up any more, even with an upgraded clutch. That diamter clutch on a single plate simply can't hack the torque that a turbo'd 1.5D would chuck out at low rev's.

27th June 2013, 11:11

std diesel clutch is not to up to it ,but a REAL uprated one would be.
is it not a 200mm clutch as in a 1.6petrol?
fit same as we fit to boosted petrol engines no way 7psi is going to make that much torque
yes the pumps mech ,but the ecu controls some of the advance with a soleniod and it sticks -so you just ignore that and move the pump so suit if causes probs .
never seen one with an egr valve on a 1.5 diesel
didn,t even have cats

27th June 2013, 11:29

Agreed, a proper, expensive clutch probably could, but that would mean peugeot would have missed their brief of a cheap, reliable little diesel town car with the 1.5D. Yup, it's a 200mm clutch, same as the GTi's. As an example, my 1.5D made 56bhp and 106lbs/ft of torque at the wheels on the dyno, with just a free flow exhaust and cheap open cone, whilst it was still naturally aspirated. Not bad for a 13 year old (at the time) car that only left the factory with 58bhp and about 97lbs/ft.

I don't doubt a turbo'd version would be chucking 200+ lbs/ft with reasonable boost. Trouble is, diesels make all the torque so low down in the revs the torque impluses to the clutch are horrible. Boosted petrols are so bad because they make their torque much higher in the rev band where the impluses are smoothed out a bit due to the revs.

27th June 2013, 14:21

Quote:

Originally Posted by axsaxoman

std diesel clutch is not to up to it ,but a REAL uprated one would be.
is it not a 200mm clutch as in a 1.6petrol?
fit same as we fit to boosted petrol engines no way 7psi is going to make that much torque
yes the pumps mech ,but the ecu controls some of the advance with a soleniod and it sticks -so you just ignore that and move the pump so suit if causes probs .
never seen one with an egr valve on a 1.5 diesel
didn,t even have cats

Mine has EGR, Electronic advance (they are all electronic advance, even the lucas pump it's just not ECU controlled) and an ECU

Also, it's a Bosch pump because it's less emissions. Peugeot couldn't use the Lucas pump from 2000/1 ish onwards because it isn't refined enough.

Quote:

Originally Posted by mechsman

Agreed, a proper, expensive clutch probably could, but that would mean peugeot would have missed their brief of a cheap, reliable little diesel town car with the 1.5D. Yup, it's a 200mm clutch, same as the GTi's. As an example, my 1.5D made 56bhp and 106lbs/ft of torque at the wheels on the dyno, with just a free flow exhaust and cheap open cone, whilst it was still naturally aspirated. Not bad for a 13 year old (at the time) car that only left the factory with 58bhp and about 97lbs/ft.

I don't doubt a turbo'd version would be chucking 200+ lbs/ft with reasonable boost. Trouble is, diesels make all the torque so low down in the revs the torque impluses to the clutch are horrible. Boosted petrols are so bad because they make their torque much higher in the rev band where the impluses are smoothed out a bit due to the revs.

I think you've got lbft and Nm mixed up there- the 1.5d produces 100Nm standard and there's no way you've gained 35Nm frm that

Diesel clutch is 180mm as standard, the same as a 1.1.

which is why it starts slipping at 100lb.ft and 90hp or so with a turbo because it's not got enough area.

You want a GTI flywheel and clutch if you're going to turbo the 1.5D, but I'm not sure how well it would idle. I'd imagine the 1.5D flywheel is quite a bit heavier.

Mine managed 61.5HP @ 4800 and 84lb.ft (114Nm) @ 1600.

the HP hadn't even peaked either

it was still climbing.

My timing is now static, and it's a shit idea. All torque down low and nothing up top. barely goes past 85mph. (used to do 100 no bother) I suggest you leave the timing system as it was.

I suggest you just do a 1.9 xud conversion... (oh wait lol)

27th June 2013, 14:53

Gah, my bad, it appears that I did mix the units on the standard output. My dyno graph is definately in lbs/ft though. Both me and the dyno operator were suprised by the change from standard. The standard exhaust and intakes on the diesel are utter crap for flow when working hard or higher up in the revs. Sorting those out ment that the car had noticeably more urge, especially in the mid and upper rev band. Mine has been off the top of the clock on a run and it was still pulling when i chickened out.

Interesting re the clutch, I'm pretty sure my S1 had the 200mm version when i had to get it changed. Also, the 1.5D is effectively the same engine block as the GTi, but with thicker liners and a different head. The crank is also the same as the GTi. I don't think the flywheel is any different either, but i haven't got a gti one to compare it too.

I am (very slowly) doing an XUD9 conversion in my old daily

. Once that's done I might lob the old 1.5D lump in my half dead saxo and turbo it, just for lols and to see what it can do with a half decent clutch bolted to it.

27th June 2013, 15:12

Nope, definitely 180mm.

You seem to forget I replaced my 2001 engine with the engine from an M reg

I thought the inlet was pretty good for flow, especially if you consider the Angle of the ports on the head itself. The inlet itself tends to bias flow to the number 1 cylinder. I guess that's because it's not central? :o

Yeah, crank, rods, block are all the same as the GTI. Only the piston crown is different, the 1.5D crown is deeper so that notches could be machined into it.

get that XUD going!!!!!!

27th June 2013, 15:21

Interesting, oh well. First upgrade for turboing a 1.5D is to chuck a GTi flywheel and clutch on then. In theory, it should bolt straight up yes?

Lol why did you do that? Just to get rid of the ecu etc?

Yeah the once in the inlet the flow is ok I guess. The airbox and intake path however.... are horrid. The exhaust free'd mine up a whole lot. Then again it was 2.5 inch straight through with only a single small box (tubular baffle) in the middle to keep it legal. Exited out the back via 2 5x4 ovals (one each side)! Not too bad at constant load but was loud as all hell when you wellied the pedal. My parents used to be able to tell which way I'd gone at the top of the 1/2 mile lane when i nailed it.

27th June 2013, 15:27

No, I've still got the ECU.

My 2001 engine broke a conrod and the crankshaft got bent as well. so that's the block written off pretty much

Found this engine in a field and it looked good. so I had it.

Ahh yeah got you now, the path to the inlet itself is bad. lol

I've got 4 individual inlets, one for each cylinder

(it's very loud) because eventually I'll be making that a custom manifold.

Yeah the flywheel should go straight on, I'm aware of 2 types of GTI flywheel bolts pattern though :o

27th June 2013, 15:37

How in the heck did you bust a con-rod in the 1.5D? They're normally unburstable, unless it got hydrolocked or something? Rotfl, found it in a field, brilliant!

Yeah sorry, should have said I was including the whole air inlet path as opposed to just the bit bolted to the head. The whole lot benefits from some decent flow work either way.

You have 16 inlets? wtf? lol! I'm guessing you mean you have no inlet manifold bolted to the head, so an individual inlet for each cylinder? lol

2 bolt patterns for the flywheel? Dammit why can't it just be easy? What's the difference in the two patterns and how can you tell one from the other? Specific to model years?

27th June 2013, 15:40

Fixed, yes one for each cylinder lol

I let someone do an oil change on my car when I was busy, and they used Fully Synthetic. Startup damage scored the main bearings over time and it eventually spun and broke.

Not sure of the Patterns

but I know the changeover is the same time as 3 plug and tapered hubs etc.

27th June 2013, 16:00

well if its got egr ,thats the first thing to block off to gain more power
I was onlyy suggesting manually sdjusting the timing if the electronic solenoid jammed --if working leave it alone

Mine managed 61.5HP @ 4800 and 84lb.ft (114Nm) @ 1600.

thats only25.6 bhp @1600 rpm --no way that should make a clutch slip if it was a good unit --yes i think it must be 180mm unit as std

27th June 2013, 16:11

Only very late ones had it as far as I'm aware. My M-reg one definately didn't have it but that's a phase 1. You could just retrofit an older pump to get the proper mechanical timing back, but i'm not sure how well the ECU would respond to that.

Clutch wise, I wonder how well an upgraded GTi clutch would stand up to a turbo'd 1.5D's torque output? Having said that, the TUD5is the most rev happy diesel I've ever driven. Must be due to being based on petrol engine internals I guess?

27th June 2013, 20:16

Quote:

Originally Posted by axsaxoman

well if its got egr ,thats the first thing to block off to gain more power
I was onlyy suggesting manually sdjusting the timing if the electronic solenoid jammed --if working leave it alone

Mine managed 61.5HP @ 4800 and 84lb.ft (114Nm) @ 1600.

thats only25.6 bhp @1600 rpm --no way that should make a clutch slip if it was a good unit --yes i think it must be 180mm unit as std

ahh right got you now about the advance. EGR closes at WOT anyway

so no power benefit, but removing EGR does stop all the oily shite blocking the inlets.

Correct? My car is standard though

clutch doesn't slip and it's fairly new.

Quote:

Originally Posted by mechsman

Only very late ones had it as far as I'm aware. My M-reg one definately didn't have it but that's a phase 1. You could just retrofit an older pump to get the proper mechanical timing back, but i'm not sure how well the ECU would respond to that.

Clutch wise, I wonder how well an upgraded GTi clutch would stand up to a turbo'd 1.5D's torque output? Having said that, the TUD5is the most rev happy diesel I've ever driven. Must be due to being based on petrol engine internals I guess?

M reg Lucas pump has electronic advance. they are all electronic advance

I can supply a picture if you want to? for reference.

Indirect Diesels tend to rev much better than Direct injection. they are also better for power, as the combustion chamber in the cylinder head allows for a slower burn, which means you get smoother power delivery on the whole down stroke of the piston.

I wouldn't want to take it past 5500 though

Compression ratio is 23:1 and I'd be scared of breaking rods.

28th June 2013, 07:05

Really? Mine definately didn't have an ecu, and the only electrical bit on the pump was the stop solenoid. Nothing else connected to the pump.

Meh, idi engines are only good for so much power before you get issues with the pre-cups. If you overheat them they tend to drop into the cylinder = dead engine. Having said that I know of an XUD9 that spins to over 6500 and has 60psi of boost stuffed down it's throat on a regular basis. I also know of one that makes 209.9hp at ~30psi and spins to 6000. Imagine that sort of power and torque in a 106!

28th June 2013, 14:11

Quote:

Originally Posted by mechsman

Really? Mine definately didn't have an ecu, and the only electrical bit on the pump was the stop solenoid. Nothing else connected to the pump.

Meh, idi engines are only good for so much power before you get issues with the pre-cups. If you overheat them they tend to drop into the cylinder = dead engine. Having said that I know of an XUD9 that spins to over 6500 and has 60psi of boost stuffed down it's throat on a regular basis. I also know of one that makes 209.9hp at ~30psi and spins to 6000. Imagine that sort of power and torque in a 106!

Lucas pumps are electronic advance, I can assure you. I never said they used an ECU to do it

think outside the box, don't you think it's weird for a mechanical diesel to have a flywheel sensor?

60Psi is ridiculous. that cannot be efficient

imagine the heat build up

XUD has a lower compression ratio than the TUD though :o so I reckon you'd get a similar percentage gain with way less boost

moar powah!

28th June 2013, 14:17

they had a crank sensor so you could set -up the injection timing by fitting a pulse senor around the injector pipe+ citreon diag tool,and need a crank sensor to know where TDC is

28th June 2013, 14:25

If you say so chap. Mine doesn't have a flywheel sensor though, I checked as I was looking to get a rev counter feed from it. The bit where it would go on the leading edge of the box is blanked off.

Yup, it was silly boost, but it went like the clappers. The lump was compound boosted with a mahoosive turbo and a big eaton supercharger. The heat build up was causing him "some issues" with the pre-cups, even with a massive intercooler. Mind you JammaPics 306 (the 209.9hp one) didn't have any issues and and went very well. It was still on stock internals and even still had the 9mm head on the pump!

By the way, the XUD9 compression ratio was anywhere between 21.8 and 23.5 to 1, dependant on variant. Most of them were 23.5:1, which is actually higher than the TUD5 which runs 23:1 as standard.

28th June 2013, 14:40

Quote:

Originally Posted by axsaxoman

they had a crank sensor so you could set -up the injection timing by fitting a pulse senor around the injector pipe+ citreon diag tool,and need a crank sensor to know where TDC is

Quote:

Originally Posted by mechsman

If you say so chap. Mine doesn't have a flywheel sensor though, I checked as I was looking to get a rev counter feed from it. The bit where it would go on the leading edge of the box is blanked off.

Yup, it was silly boost, but it went like the clappers. The lump was compound boosted with a mahoosive turbo and a big eaton supercharger. The heat build up was causing him "some issues" with the pre-cups, even with a massive intercooler. Mind you JammaPics 306 (the 209.9hp one) didn't have any issues and and went very well. It was still on stock internals and even still had the 9mm head on the pump!

Well, my M reg (car was registered in late 1994) Lucas pump has electronic advance

It's a black spring return solenoid with 2 pin connector, and I'd say that's pretty early. It also had a crank sensor on it, I think I might still have the loom I should go and trace the wires. My TUD5 Workshop Service Manual doesn't really cover the engine loom itself.

Yeah I heard Eaton's aren't great :/

The DTurbo Bosch pump fits on the TUD5 engine apparently. There was a guy in Malta who fitted that to his 106.

28th June 2013, 15:18

My s1 is also a late 94 reg on an M, with a Lucas pump! Gotta love pug build inconsistencies! lol! The only electrical connection to the pump on mine is to the stop solenoid.

I should also go ahd have a look at the lump again as mine is out of the car so all (relatively) accessible.

The eatons are ok if you don't ask them to flow a lot of air at high boost. The compund setup I was talking about actually worked quite well because the eaton was suppling a bit of boost low down in the rev's whilst the turbo got wound up. It was then increasing the boost provided by the turbo so the turbo didn't have to try and flow big air at high boost pressures. As you said though, heat was an issue.

Yeah I think I've heard about that one. I think his is the one that is on 106oc that i was on about earlier. Where the DTurbo bosch pump fits, the lucas version will as well, although whether you'd want to is another question! Chucking the bosch pump on my old 1.5D and slinging it into the saxo was my plan after I've finished the XUD9 conversion on my 106.