Missfire/hesitatation

[Henry 1.9GTi 36]

Started a few days back; slight hesitation around 3k RPM but only did it once or twice. Got more regular the next day. And finally today it got really bad and is now perminant hesitation everywhere in the rev range. It will go miss-ok-miss-ok-miss etc.. if I give it some beans but only did it once as it sounds truely awful. Had to nurse it home for 7 miles.

 

No power at all and sounds horrible with any load applied. Sounds like 3 cylinders at idle.

 

I will check spark, compression and replace the AMP for one that was working a couple of years ago but can anyone give suggestions. I have seen through search that amp, coil and AFM are a good place to start.

 

Thanks.

Henry.

[Henry 1.9GTi 36]

anyone know the correct coil for the XU9J4? Closest I can get on servicebox is 5970 43 which says for XU9JAZ since series 08819069.

 

Are they available from eurocar parts or GSF with decent quality. Or does anyone know the pug dealer price.

 

Cheers.

Henry.

[wracing 19]

if no ignition issues, then im betting head gasket or valves not seating correctly. hopefully it will be a duff amp or something easy.

 

when you take the plugs out look at the colors that will flag possible gasket or timing issues especially if you running a 3row ecu with a lamaba

 

the reason i reckon its a gasket is because mine did the exact same thing the gasket had blown in between 1 and 2, plugs 3,4 black as anything 1,2 wet as anything (with petrol)

 

dont drive it untill youve got the issues sorted, i f***ed my head driving it home

 

best of look mate hopefully nice and simple!!

[welshpug 1,666]

water around the spark plug wells?

Edited March 6, 2009 by welshpug

[Anthony 1,003]

anyone know the correct coil for the XU9J4? Closest I can get on servicebox is 5970 43 which says for XU9JAZ since series 08819069.

You can use a Phase 2 8v coil for testing if you've still got the one from your old engine - there's no bracket to attach it, but the wiring and HT connection is the same.

 

water around the spark plug wells?

Or oil - the XU9/10J4 engines suffer from this when the seals under the rocker cover shrink with age.

 

Worth checking/swapping the HT leads, and check the dizzy cap too - if the car has been stood then damp can get in and cause problems, or the center pin can stick in.

[Henry 1.9GTi 36]

compression at cold crank showed, 190, 195, 200, 180 PSI

 

There is spark at all four plugs, 12v at each injector lead and no damp in the dizzy cap. Pin is free and I cleaned up the posts.

 

Unfortunately I can't find my other amp and I don't have anything else off the old engine including the coil.

 

If the amp was on its way out would you still see spark at each plug? Is there any possibility that the ignition timing could be out on a 3 row motronic with no oxygen sensor.

 

The plugs looked the same as the always do, no water or oil around the top. Some slight oil residue around the washer on the combustion side I think but nothing drastic.

 

Thanks for replies, keep em coming

[Jon_Bmw 13]

My friends had a similar problem, it was running on three pretty much the whole time, so it was easier to isolate the problem to a particular cylinder.

 

To cut a long story short, it turned out that cylinder 1 (the one closest to the gearbox, not sure if you call that 1 or 4) was the one that was in op. It was the HT lead, but when checking for a spark on the plug it all seemed hunky dory as the HT lead would 'reconnect' internally. As soon as you put it back in, it was effectively 'breaking' and therefore running on three. This shortest HT lead is quite common to fail I suspect as it has to make a nasty bend. Worth trying a different cable for piece of mind anyway.

[welshpug 1,666]

check the wiring to the injectors, namely the pins in the plugs

[Henry 1.9GTi 36]

all seems ok, as said I saw 12v at each and i pushed the female pins closer together for good measure.

[Henry 1.9GTi 36]

well put everything back and started her up, all was fine so went for a drive after about 2 mins the hesitation began and after 5-10 was missing again.

 

Going to pick up a new coil and some HT leads tomorrow morning. And a local bosch supplier has an ignition module on the shelf but its £50!

 

will update tomorrow.

 

Henry.

[Jon_Bmw 13]

If you fancy a longish drive to salisbury, you can test out the bits on my car as its not going anywhere tomorrow. Swap things over till you find what is at fault. I have spares, but I can't really sell them, as I need them really for any unforeseeable things happening at track days.

 

The offer is there, anyway.

[Henry 1.9GTi 36]

thanks for the offer but its a bit far to go with a poorly engine.

 

I have picked up a coil which turned out the be an intermotor part, will see how it goes. HT leads are a joke so there going straight back. Got a new ignition amp but I might be cheeky and take it back if its not at fault.

 

Henry.

[Henry 1.9GTi 36]

well turned out to be dodgey injector wiring. oh the joys of this loom again. Must owe me at least £500 now... plug n play hmmmm

 

anyway, wires from the engine loom were soldered to injector plugs/wires and then heatshrinked. Luckily when my dad came home we had a look and decided to pull injector plugs off to find which pot was missing. Only when I went to pull one plug it suddenly ran fine. Wiggleing the wires showed up the missfire. So we stripped bk all the wiring and found the soldered pieces. Three pulled apart with no effort at all and the others looked a bit dodge. So all crimped up now and working fine.

 

Another note, I bought a brand new £50 BOSCH ignition amp to try and eliminate a few things, it wouldn't let the car rev above 4k. Put the old one bak and all was well again. Cheers bosch!

 

Thanks for all the replies.

 

Henry.

[Miles 331 1 Cars]

Good to hear you found the fault,

 

So the plug's had been cut off another loom and soldered on?

[Henry 1.9GTi 36]

looks the way of things Miles, no idea why. Car wouldn't run after the engine went in, and after trying various electrical goodies i had to give it to a garage to sort. (which cost more than the loom itself!) This also turned out to be the loom; wasnt letting enough current to power injectors and relays due to a heavily corroded connection. But did show continuity which was baffling inexperienced me.

 

It also cranked the car without turning the key to 'start' when i first got it lol. oh joy can't wait to get the GTi-6 inlet on it with a nice shiney new loom and ecu.

[Anthony 1,003]

It also cranked the car without turning the key to 'start' when i first got it lol. oh joy

That's a common one, as Peugeot swapped the starter and ignition wire positions on the multiplugs between Phase 1.5 and Phase 2, so a loom wired up for one won't work on the other unless you swap the two wires over - if you don't, you get the exact problem you experienced.

[S@m 156]

 

 

Another note, I bought a brand new £50 BOSCH ignition amp to try and eliminate a few things, it wouldn't let the car rev above 4k. Put the old one bak and all was well again. Cheers bosch!

 

 

Thats strange, i had that exact issue with a brand new intermotor amp, but putting the old, dirty, rather sorry looking bosch amp back on sorted it right out, did you make sure to smear the heat transfer paste on the back on it? seems they dont like working without it, in my experience anyways.

 

Sam

[Simes 248 2 Cars]

Another note, I bought a brand new £50 BOSCH ignition amp to try and eliminate a few things, it wouldn't let the car rev above 4k. Put the old one bak and all was well again. Cheers bosch!

 

Thanks for all the replies.

 

Henry.

 

I spent ages tracking down a similar fault (whole thread on it) and replaced the plugs, cap, arm, plugs and ignition amp pnly to find out it was a dodgy lead.

However I did buy a brand new bosch ignition amp and tried three other spares which all showed the same signs ie. limiting the revs to 80-0 rpm or 3.5k rpm. Weird isn't it.

Stuck with one a forum member sent me.

[CaptainK 11]

To cut a long story short, it turned out that cylinder 1 (the one closest to the gearbox, not sure if you call that 1 or 4) was the one that was in op. It was the HT lead, but when checking for a spark on the plug it all seemed hunky dory as the HT lead would 'reconnect' internally. As soon as you put it back in, it was effectively 'breaking' and therefore running on three. This shortest HT lead is quite common to fail I suspect as it has to make a nasty bend. Worth trying a different cable for piece of mind anyway.

+1 I had similar with my old 1.9 engine causing it to run exactly as the original poster said. Turned out to be a HT lead problem similar to what you said.

[MerlinGTI 3]

Intresting indeedy.

 

I had the missfire at 4k problem with a seccy hand duceller amp, So I too bought a new BOSCH one and got the same thing, my old BOSCH one gave no missfire.

 

Convinced the new amp and the very clean looking Duceller were not at fault when compared to my old scorched tatty BOSCH one, I was advised to try another seccy hand dizzy (same part number as my old one)

 

I did this and now its fine with the new BOSCH amp that previously gave a missfire at 4k. There was TONS of play in my old dizzy as well.

[Henry 1.9GTi 36]

I did take the dizzy cap off and give it a clean but it was pretty dry in there, posts were corroded but gave them a quick scrub up. The rotor had no play in it so just left it as is. I have an invoice for a new dizzy cap rotor and insulating plate thing from when the engine was built ~ 20k miles ago so I would expect them to be in ok nick. They are all duceller items btw.

 

tbh ive had it with the Mi management, i'm sure its great for a standard lump when its all spanking new. But with my head and cams idle is pretty rotten and it doesn't feel any more than the standard 160bhp. Its pretty much untuneable as far as the ignition advance vs load is a set curve (designed specifically for the standard engine) and fueling adjustments are crude. I'm just really hoping for a summer job so I can treat it to a new ecu, loom, balanced injectors and a gti-6 inlet then hopefully it should make ~190bhp.

 

also thinking my grpN exhuast is a bit restrictive at the back box, pipe is tiny and feels like a battering ram when you put your hand newhere near it at idle, hate to think of the gas speed/restriction at 6k+ rpm.

 

sorry just like to rant then dream