Right, this has been going on for a long long time now, have a miss-fire which i just can't shift...

 

New plugs, cleaned all connectors, checked and corrected timing, replaced coil packs, replaced almost every vac/fuel pipe, plus many other general tidy/renewing type things...

 

Revs fine when not under load, but, think it isn't as smooth as it should be, and when driving, put ya foot down, all noise no go, (just fitted new clutch too, not slipping) no torque and pathetic at low revs, and misses/back fires, so i'm ok that it's fuelling, seems to be a spark issue... Also tho, does seem to behave a bit better afetr about 3500 revs, when the engine gets a bit of momentum behind it...

 

All cylinders are sparking nicely, until you put a load on it. Checked the ECU connector, that is where i am thinking the problem could lie. All I had to do was touch the connector with my finger progressively harder, but not very hard at all really, and it would drop down to 5, 4, 3 cylinders, stop... The loom has been butchered a bit, guessing it's where the alarm was fitted, have neatened most of it up, and fettled the plug, and now can waggle the ECU or whatever and no change what-so-ever, but, still misses under load, and also the ECU is pristine inside, no dry joints etc....

 

Getting a little frustrated now, will never get to my wits end, love the car, just wish I'd had it drive-able in the 2 years I've had it! (Have been working away a bit, and done full engine re-build and manwell conversion, plus fixed countless botched jobs on her, so not all bad)

 

Any suggestions? Only thing I haven't changed really is the PTU, don't really think it's that tho, does it when the engine is cold/hot, temp makes no difference, oh, and also, no error codes, 55..........

 

ANY help at all is much much appreciated, sort this out then MOT and daily drive time, massively overdue and greatly anticipated! I'm wondering if conzult could tell me something, but i haven't got it, can't drive the car, and not aware of anyone with it any where near me!

 

Cheers guys, apologies for the essay :-)

have you checked your MAF sensor? or if there is any air leaks between the gasket and the air filter? mine would loose power and sometimes cut power altogether when revved because the MAf was not tight enough

will check tomorrow matey, cheers, keep em coming guys!

Try a different PTU mate, mine was like this until i changed the PTU! They get heat damaged and they stop transmiting signals! Try a good working series 1, or get a nice series 2!

Well, makes sense, that is pretty much the only thing I haven't changed! And missing is a symptom... Anyone got a working spare they wanna lend us, will buy it if it cures it?

Would def check connection around the maf and clean it etc, tony another forum member near me had a hesitation issue under acceleration , and swapping my maf with his seemed to cure the issue

 

 

after a good clean of the connector all seems well

 

worth a shot?

This sounds either like MAF or timing, get both checked out.

The electronic timing is fine, calibrated it with a strobe, was slightly out, and mechanical timing is fine I'm sure, I fitted the belt ;-)

 

It's almost as if it's running on 5, but not as bad as that, a bit too much vibration i think, should be smoother, but it's not on 5, unplugging each coil packs drops a cylinder out.

 

It's annoying as I don't know anyone else who has a Zed, and never ever see any at all around this way, and I have nothing to compare it to...

 

Ah well, the search will continue!

Have you checked your TPS voltage? Can make a huge difference on these stupid cars.

 

Sad to hear the coil packs didn't solve it though :(

Yeah, have checked that too, set it correctly :-(