Misfire/cutting Out.

[Guest Gidz205]

Right, i've got a (87) 1.9, standard engine and having read through 74 pages of threads have come to the conclusion i am not alone with this problem! (hopefully...) It's Not just a misfire, it can go from 4 to 3 cylinders firing to none at all then back to normal again (it's almost like an immobiliser's engaging-it's not fitted with one) it'll do this from 2,000rpm sometimes and sometimes it'll run fine all the way through the rev-range then give up, it doesn't cut out, it even keeps running if a dip the clutch.

 

I've replaced the plugs, oil filter, air filter, fuel filter, (the HT and LT leads seem fine), i've checked all the connections on the coil, dizzy and injectors are attached properly, gently sanded the connector on the coil down with wet 'n' dry, checked all electrical connections are attached properly and it STILL won't run properly. Any ideas other than driving it off a cliff? Also, at the risk of sounding like a plonker, where's the ignition amp located as alot of people on here think it might need changing from a misfire but i've no idea where it is!

 

Cheers...

 

Gidz.

[jackherer 543]

The ignition amp is a big blue chip thing on the inner wing normally.

 

Sounds like the air flow meter to me though, take the hose off it and check the vane moves freely and smoothly.

[Guest Gidz205]

thanks man, i got it revved up with my head under the bonnet a matter of moments ago and the gate inside the airflow meter seemed responsive. however, in doing so i've realised that i've nicked a tiny hole in the fuel pipe in fitting the new fuler filter!!! cut it off with molgrips and wait for the engine to cool before i can sort that now. D'OH! Also, there's no 'big blue chip thing' on the inner wing, there's something that looks like a relay with 'cartier' embossed on it. presumable this isn't for the clock? ;P

[Paul_13 212 1 Cars]

It could be a really expensive ignition amp encrusted with diamonds lol.

 

Normally it's left of the fuel filter and just underneath the bonnet prop. It will be mounted on a plate of metal unless someones moved it.

[Tom Fenton 1,548]

Air flow meter would be my guess. Easiest way to check is to substitute with a known working one. Note that it needs to be one from another 1900, the 1600 one is not the same.

 

It could also be the ign amp, but sounds exactly like the problem I had with the air flow meter.

[Guest Gidz205]

Thanks for the help guys, all i need to do now is source an air-flow meter. Also, hate to be a pain in the arse but the leaky fuel line into the fuel pump now has an inch split in it lengthways, it appears to be like a double skinned high pressure hose, would it be cool for me to cut the split end off it and reattach the eye back on to it or is the hose specifically made to accomodate the eye on the end?

 

I'm sorry to be a massive pain in the arse and be a noob loaded with multiple questions but i really have no idea where else to go other than my well thumbed haynes manual. This is no two spanner job.

 

also, no ignition amp, whatsoever. strange.

Edited June 1, 2009 by Gidz205

[nick 3]

All the ignition amps I seen have been on the right hand side inner wing, near the bulkhead... never seen one on the left hand side?? If it is std it will definitely have an amp (which is my guess as the cause of the problem)

 

Nick

[welshpug 1,666]

They can be situated on either side, up to about 1991/92 they were on the left hand turret with the coil, on later engines they were on the right hand strut with the coil bolted to the inlet manifold.

[nick 3]

Ah righto... didn't know that, so gidz' will be on the right then ('87)

 

Nick

[Paul_13 212 1 Cars]

All three GTI's i've own have been at the back left of the engine bay as you are looking at it from the front.

[MrG 3]

I have an 87 GTI and the amp is on the right (as you look under the bonnet) behind (or underneath) a black plastic cover next to the cylindrical coil near the battery. Its screwed to an ali plate. Pain to get to but doable. One question on this, Mr Haynes says no heat paste is needed in this location? I thought you had to put paste on regardless?

Edited June 2, 2009 by MrG

[jackherer 543]

The Haynes is wrong if it says that, sometimes some fresh new thermal transfer paste on a cleaned up amp and heatsink will solve an intermittant missfire. Its always worth trying as the original Bosch MTR01s seem to be a lot more reliable than the aftermarket alternatives.

[Guest Gidz205]

Turns out i had a replacement airflow meter in stock and it is now running perfectly, or as well as a 23 year old french car can i suppose. thanks for the help, much appreciated!