Z22SE misfire/intermittent rough running

#1
Please can anyone help me with what appears to be a misfire with my Vectra B zz22se engine.
I am not a mechanic, but after going to several garages, in desperation I'm posting this info on your website for possible help get my engine working correctly.
Car was registered in May 2001, and I have owned the car since May 2003. Mileage 105000.

Problem....

Slight misfire on idle. RPM needle drops occasionally from 800 for a second then restores back to normal. Does this every 20-30 seconds at idle.
From cold, engine performs ok up to temperature. Can achieve high revs ok. Does not stall, but still has misfire on acceleration and idle.

Stop and start from normal working temperature, and engine performs as above, relatively ok, but if I stop and wait for approx 5-30 mins, when starting up misfire gets worse, especially about 1800 to 2000 rpm, and the car sometimes runs like the "choke" has been left out ("showing my age"). Very noticeable under load and uphill.
This will be the same throughout the remaining part of the journey even if I stop and restart. Only if I let the engine cool down, like overnight, this bad misfire disappears, and reverts back to the slight misfire mentioned above.

This problem began about 18 months ago, when the ecu warning light indicated on the dashboard, I took the car to Vauxhall main dealers in Bournemouth, who said that it could be one of 10 different problems, ranging from stretched timing chain, throttle unit, ogr valve, ecu, etc.
They had the car for 2 days and could not rectify the problem unless they changed all these parts costing over £2500, but they would check the timing chain to see if it had stretched or jumped. It hadn't and they reported it as ok and told me to come back if the misfire got any worse!

Then 12 months ago, started up as normal, drove 20 miles, stopped for 1 hour, and after re-starting there strong smell of petrol and car was running rough. Managed to limp to the nearest garage and were told that it was running on 3 cylinders. Coil pack, leads and plugs were renewed. Also OGR was replaced as egu code was indicating this at the same time.

Got the car back, still had the slight misfire. Went back to the garage who said that they cannot find the misfire fault, as no current codes from ecu.

Ecu light came back on. Friend had obi tester, plugged it in and gave the code for a camshaft sensor fault...p0340. Tried to find this on my zz22se engine but could not find it.

Car continued to run as before with misfire. Then one night, car ran rough as above, bad smell of petrol, etc. Relayed car to 3rd local garage, only to hear that they could not find anything wrong with the car the next morning when it was started from cold, apart from the slight misfire that they could not isolate and gave the same reasons as Vauxhall as to why the ecu light was on.

2 weeks ago, car started running very rough again. Sent the car to the garage, who stated car was running on 3 cylinders again and 3rd coil pack, plugs, and lead were changed.

Asking why this keeps happening, and ecu was blamed for possible coil failure, and recon ecu was swapped over.

Got the car back and guess what, car still misfiring as before, but running. Now waiting for coils to go faulty again so car ends up running on 3 cylinders!!!!!!!!!!

That was Friday, and car will be going back to garage who swapped out ecu on Monday, having to take another day off work!!!!!

Reason I'm writing this is because I don't know were else to get advice from after going to Vauxhall main dealers and 3 or 4 independent garages I'm still left with faulty engine.

Any, please, any advice or possible contact to an experienced Vauxhall mechanic would truly be very helpful.
Thank you for taking the time to read this article.

Jim
 
#2
Hi did you get to the bottom of this problem i would personally try replacing the coolant temperature sensor first it effects your cars fulling when faulty could be why the car runs fine when cold hope this helps
 

evocarlos

Stupid Bollocks
Staff
#4
the car when cold runs from a fueling table in the ecu (while the heater in the lambda sensor warms up)
for me i would be looking with op-com at the lambda readings to make sure you dont have a faulty front sensor

the cam sensor code is the coil pack as the z22se dont have a cam sensor its mimicked by the coil pack to the ecu

it sever cases i was always told to look at the specifics of what makes an engine run
fuel/air/spark if you have air ok if have fuel ok if you have spark then it should work :)
 
#5
the car when cold runs from a fueling table in the ecu (while the heater in the lambda sensor warms up)
for me i would be looking with op-com at the lambda readings to make sure you dont have a faulty front sensor

the cam sensor code is the coil pack as the z22se dont have a cam sensor its mimicked by the coil pack to the ecu

it sever cases i was always told to look at the specifics of what makes an engine run
fuel/air/spark if you have air ok if have fuel ok if you have spark then it should work :)

Thanks Evocarlos for your advice, most appreciated. I'll go round to the garage some time this week and ask them to look/measure the lambda readings. Also have had replies from Burnzi and Chill regarding temp. sensor and throttle body. Will also investigate these as well. I will let you know next week on how I get on. Again thanks for replying to my problem.
 
#7
Hi did you get to the bottom of this problem i would personally try replacing the coolant temperature sensor first it effects your cars fulling when faulty could be why the car runs fine when cold hope this helps
Thanks Burnzi, I'll try this and change it over. I'll let you know how I got on next week....Cheers
 
#10
Did you fix your car at the end?
I have not seen this guy comment on here for a long time now, Most likely moved on to a new car by now?
There are only a few of us on here now who have been using this site for some time. A lot have switched to using the FaceBook group but that's harder to follow what's going on.
 
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