Slight hot idle misfire? Cannot find OBD port

13th October 2013, 18:41

Hi all

Got an ever so slight misfire on hot idle. I wiped the plugs out this morning and replaced them with like for like NGK BKR6EZ. All went in nice, little copper slip and torqued to 25Nm.

The old plugs look old but the combustion looks almost perfect. No oil etc. Car is on 66K.

I can still feel an ever so slight mis-fire on idle, when hot. Weirdly, this seems to be more prominent when the fan kicks in?

I was also unable to locate the OBD port on my 1997 MK1 VTS. Does it even have one? Definitely has a MIL lamp on the cluster, although it's not lit.

I can also see no measurement for air mass on the intake side, but can see what appears to be a MAP sensor on the back of the '16v' inlet manifold. Is this what they use? Speed/density for airmass rather than a MAF? A bit like my two Hondas if they do.

Advice appreciated!

Cheers

Don

13th October 2013, 19:59

There's no MAF only MAP on saxo's.

ODB socket is by bonnet release, although on a 1997 car you'll need Lexia (specialist Citroen software).

There's a possibility of a fault with the coilpack - these tend to show their head moreso when the engine is hot.

13th October 2013, 20:17

Sounds like the coil pack could be needing looked at/replaced.

These usually break down with heat. Try changing the plugs for some Bosch/Denso onesm it could be that your current plugs are going high resistance with age, and the coil pack (not being new anymore) can't quite jump the gap.

Yes, ALL Saxo's use MAP sensors

Having a 1997 car, I can't remember the pinout, but you can bridge 2 connections on the OBD port and you can count the EML flashes.

Can't do that on OBDII models I don't think, but you can with OBD.

13th October 2013, 20:35

Does this help?http://www.autodiagnos.com/sites/def...citroen_ad.pdf

13th October 2013, 20:57

Cheers guys

OK so it appears it just had a new ignition coil last month. Just digging through the immense service history lends itself to a receipt for a 'Mobiletron' ignition oil pack. Who the hell are they?! I don't like cheapo ebay goods. Had bad troubles with replacement ICV's for a MK2 GTI 16V which had the car running at 1300rpm!

When I changed the plugs today after the engine was warm I could see a brand new coil unit which I removed. I also changed the four retaining screws for some nice stainless M5 ones as the torx heads looked a bit rounded.

The coil unit did, however, smell 'electrical' if that makes sense? It smelt of warm electronics, not the smell I like on new electronics to be honest.

Almost all of these cheap lambda sensors, MAF sensors etc on ebay are a complete and utter waste of time.

Tomorrow I'd going to change the ignition coil for a genuine OEM unit. Anyone know how much these sell for? I have seen Lucas ones which are cool but I quite fancy a genuine Citroen one for this.

Oh, and there is no OBD plug under the passenger side of dash behind the fuse cover.

13th October 2013, 21:24

Is it too old for an obd port?

13th October 2013, 21:31

Quote:

Originally Posted by M_Rust

Is it too old for an obd port?

All saxo`s have a diagnostics port.

13th October 2013, 21:37

Ok I don't know much about saxos but I know some cars depending on age (pre 2000 I think) don't have them

13th October 2013, 21:45

Quote:

Originally Posted by Jungledon

Cheers guys

OK so it appears it just had a new ignition coil last month. Just digging through the immense service history lends itself to a receipt for a 'Mobiletron' ignition oil pack. Who the hell are they?! I don't like cheapo ebay goods. Had bad troubles with replacement ICV's for a MK2 GTI 16V which had the car running at 1300rpm!

When I changed the plugs today after the engine was warm I could see a brand new coil unit which I removed. I also changed the four retaining screws for some nice stainless M5 ones as the torx heads looked a bit rounded.

The coil unit did, however, smell 'electrical' if that makes sense? It smelt of warm electronics, not the smell I like on new electronics to be honest.

Almost all of these cheap lambda sensors, MAF sensors etc on ebay are a complete and utter waste of time.

Tomorrow I'd going to change the ignition coil for a genuine OEM unit. Anyone know how much these sell for? I have seen Lucas ones which are cool but I quite fancy a genuine Citroen one for this.

Oh, and there is no OBD plug under the passenger side of dash behind the fuse cover.

Are you sure? If you sit in the passenger seat, it should be just above your left ankle. "on" the A pillar, behind the dash. it's nowhere near the fuse box, it's below that.

All Saxo's have the OBD connector.

Only Peugeot 106's from 1991>1996 have the 2 pin connector under the ECU - which you bridge and read the EML flashes from.

13th October 2013, 22:03

OK I'm looking in the wrong area like a tool lol

I have an Autel OBD scan tool - I just hope it can mate to the older protocol the Saxo probably uses.

I'll look again!

14th October 2013, 13:44

Quote:

Originally Posted by MartinObviously

Are you sure? If you sit in the passenger seat, it should be just above your left ankle. "on" the A pillar, behind the dash. it's nowhere near the fuse box, it's below that.

All Saxo's have the OBD connector.

Only Peugeot 106's from 1991>1996 have the 2 pin connector under the ECU - which you bridge and read the EML flashes from.

On mine its directly above my right ankle(knowhere near the pillar)lol.

14th October 2013, 19:04

Quote:

Originally Posted by stevo67

On mine its directly above my right ankle(knowhere near the pillar)lol.

What the fuck.

typical Peugeot/Citroen inconsistency right there.