misfires??

[C15]

Hi All,

have a problem with my 4.2 Engine.. it started running like a 5-7 cylinder whilst standing in the queue at the Chunnel on the weekend, so had to turn around and go home... The car suddenly then ran perfectly, then again started missing.

Not sure what the cause is, as it now also only starts after flooring the throttle a while. I am going to replace all the usual suspects: Coils / Leads / Plugs, anyone else got any ideas what else I should be checking? would a dodgy fuel pump or just plain heat cause a similar issue?

(Is it correct that the coils are Beru - BER-0040100341/5, Fiat Ulysse / Citroen ZX, OE:5970.60)

Recently the manifold (Stainless) snapped so had it re-welded and pressure checked. I know loose manifold bolts could cause the issue, (checking them as best I can showed they were tight..

Thanks for any tips..

Stephen

[Gazzab]

Make sure you buy quality coil packs.

[pulsarboby]

shame about that steve having to turn back and all.

im no cerb guru and others much more knowledgable than me may be able to shed further light but i would do as you suggested by checking ignition system first and replacing any possible defective items such as plugs, leads, dizzycap, rotor arm etc.
it could be that the car is overfuelling and temporarily flooding a plug when it gets hot.....is there any black smoke on acceleration when this happens?
does the engine oil reak of fuel?
have you got a kv meter to check spark strengh and ht lead resistance?

could also be fuel evaporation i guess but what ive said above will determine that with regard to black smoke or lack of it!

could also be a dicey injector which isnt atomising correctly or lambda sensor, but once youve replaced the general service items, then its time to look a little deeper if prob still exists

[gerradiuk]

I had the fouling plugs last week, I had been using it more than usual but on silly short trips & lots of waiting in jams etc. The plugs were fouled.

[Rawhide]

[redacted]

[Tanguero]

pulsarboby said:

im no cerb guru and others much more knowledgable than me may be able to shed further light but i would do as you suggested by checking ignition system first and replacing any possible defective items such as plugs, leads, dizzycap, rotor arm etc.

Have you checked the dizzy cap and rotor arm on your Cerb recently?



OP - Sounds like typical coil problems to me. The number for the Citroen coil packs is in the equivalent part numbers thread. Some people swear they only get good results from the Bosch coils, but personally I have never had a problem with Citroen ones. You pays your money and takes your choice.

[ukkid35]

Tanguero said:

Some people swear they only get good results from the Bosch coils, but personally I have never had a problem with Citroen ones. You pays your money and takes your choice.

And I've had a year out of the cheap Chinese £25 ones (or you could pay £100 each for the Bosch ones).

[pulsarboby]

Tanguero said:

Have you checked the dizzy cap and rotor arm on your Cerb recently?

yep sorry blond moment lol

[C15]

Does anyone have a part number from the Bosch coils, I've asked Bosch. It they say apart from very expensive Motorsport 2x2 ones they don't make ones for a Citroen ZX?

It seems Beru (German manufacturer in Stuttgart) are the only ones who made them.

[sweeper]

This thread might be of help

http://www.pistonheads.com/gassing/topic.asp?t=828...

[ridds]

Plug the thing in to a laptop first and get some pointers before spending more money.

You've replaced all the ignition parts yet it could be a lambda sensor of throttle pot issue.

Also, if you had low fuel and no A/C or A/C not running the fuel could be very hot and cause your poor running conditions.

I had a similar issue at the ferry one year, ran really poorly when pulling up, stalled trying to manoeuvre to a new booth and then when I tried to restart it back fired and would not restart. Flattened the battery and got an RAC man to give me a boost. Floored the throttle (zero mapped fuelling so cleared it out) and then it was OK. Filled the tank with cold fuel the other side and all was gravy.

[C15]

ridds said:

Plug the thing in to a laptop first and get some pointers before spending more money.
You've replaced all the ignition parts yet it could be a lambda sensor of throttle pot issue.
Also, if you had low fuel and no A/C or A/C not running the fuel could be very hot and cause your poor running conditions.

The car is the Griffith; CliveF converted and has an emerald ECU & Lambda display in Glove box (No A/C).. The Sensor is reading between 13-20 as it always has, dependent on state. I haven't checked the ECU readings as don't have a laptop with a series connector; and not being in UK with the car am leaving it until later in the year.
The parts are not expensive to replace, so doing it just for piece of mind.

Cheers everyone for your input
Stephen

[C15]

sweeper said:

This thread might be of help

http://www.pistonheads.com/gassing/topic.asp?t=828...

Cheers... reading the thread it seems they tried an intermotor type.

Here are all the comparable part numbers after a long search in OE catalogues.

OEM Numbers (Citroen, Lancia, Peugeot, Fiat)
96 074 054
96 165 970
96 074 054 80

Chinese Makers
5970.48
5970.60

BOSCH (incl. obsolete)
0 221 503 004 obs.
0 221 503 007 obs.
0 221 503 422 obs.
0 221 503 025

BERU
BER-0040100341

BREMI
11882

Intermotor
12613

For those who don't know who Beru is: It is actually the Electrical System unit of Borg Warner, the inventor of the glowplug...


Having checked the Bosch dealer website this morning again wide awake... found the Bosch article..
Ignition coil -
Independent aftermarket part number; 0 221 503 025
Type formula ZS-K 2x2
Cost: £57 incl.

If you want a better one, the Bosch Motorsport version 0 221 503 407, however for this you need an ECU with four internal ignition power stages. (Whatever that means)... As it doesn't have an integrated transistor, which is the bit that fails with high temperature. Big problem, only compatible with Bosch Jetronic.

Edited by C15 on Tuesday 21st August 08:31