What could this be ?

12th January 2012, 18:36

I've got a 98 1.1 saxo. Its been running fine but recently has started to show some issues.
It'll run fun for 10 miles to work no problems but then the next day or on the return jouney after the car is fully warmed up after about 7/8 miles it'll start jerking and losing all power for a second. I pulled upto the lights on the way home and it idled fine for a minute but then suddenly sounded raggy as anything almost like a diesel and the exhaust was rattling loudly as though the engine was just before stalling.

It has never done this when the car is cold only when fully upto temprature but that could just be coincidence.

Fule pump /filter issue maybe ?

Cheers for any advice

12th January 2012, 18:41

Sounds like mine did when the spark plug snapped in the head, but because the spark plug snapped the coil pack didn't sit right...so it could be either...

12th January 2012, 18:42

Id say coilpack is failing tbh, but could be lucky with a spark plug

12th January 2012, 18:46

The Mrs 206 1.1 was exactly the same, turned out to be the coolant temp sensor (blue one) try unplugging it for a couple of days.
It was fine running cold, then sometimes it would give your sypmtoms, but only occasionally, then it would be like it every journey once warmed up.
But try unplugging it when it starts to do it. Only a 2 min job to replace it too.

13th January 2012, 00:26

Can i use any block type coilpack or do I need a specific one?

if that doesn't work I'll try changing the coolant sensor

Cheers for replies

14th January 2012, 12:37

Which type of coil pack does your car use?The block type on the end of the cylinder head or the one which fits over the spark plugs mate?

14th January 2012, 13:35

My bet is on temp sensor as you say it happens when It's warm.

14th January 2012, 16:55

Its a block coilpack.

I thought that if the revs drop to correct idle speed when the engine is warmed up then the coolant sensor is working properly but could be wrong.
Suppose it could also be the crank shaft sensor (could be bloody anything with these cars ). My flywheel has worn teeth on the ring gear but I dont suppose this would affect the crackshaft sensor reading.

Wondering if it might be worth getting a diagnostic check or might just see if I can source a cheap coilpack and crankshaft sensor and hope for the best.

Cheers

29th January 2012, 15:12

Well relaced the coilpack (new) and still does it on journeys where the engine gets fuly warmed up but only sometimes.

Thinking about replacing but one at a time

Crank sensor
HT leads
Green coolant sensor

I do get yellow gunk (very,very slightly) in the filler cap and i have the classic oil leak at left side of head would a failing headgasket cause a misfire when car is hot.

Cheers for any advice

29th January 2012, 15:18

My bet is still coolant temp sensor. My vts has been steadily getting worse over the last week. Coughing spluttering when warming up, when its hot it was okay. Changed the blue sensor today with one I had in another Peugeot engine and all is well again.
I'd get down the scrappy and robb all the sensors you can from pug Citroen engines

29th January 2012, 18:49

The yellow gunk sounds very much like a failed headgasket, lucky for you an 8V headgasket is cheap and easy to do. And if you already have an oil leak, it would be worth replacing