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Hello,
I have a 2004 VW GTI 1.8t.
I am getting a cylinder misfire on #2. No Service or work done before hand. The car is new to me (~3 months)
I feel it is the injector, here’s why.
I have swapped coil packs around (coil over plug design), I have pulled the coil pack out (with spark plug installed) cracked and saw spark.
I am getting battery voltage on my supply wire at the injector.
A friend has let me barrow a handheld oscilloscope. I am unsure of how to hook it up to look at the injector pulse.
I’ve watched the ScannerDanner injector videos on youtube, but I either missed it, or it wasn’t mentioned how to hook up the scope.
I know the injector is ground switched.
I know he probe goes on the ground side (signal wire) or the injector. But being Ground switched, where do I ground the scope?
Thanks a bunch.
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[quote=”wysetech” post=61518]Be very sure you have good constant spark on each coil as these were a problem area.[/quote]
Thanks for the reply.
I am aware of the coil pack “cracking” issues. However, I’ve swapped coil packs around and issue doesn’t move, stays on #2.
either take a long screw driver and put one end on the injector
and the other to your ear to listen for the injector clicking or use
a noid light to read injector pulse.When does the misfire occur? Cold start? Hot start? Is it a static dead miss? When accelerating, and how hard? How do you know it’s #2? ECM stores P0302?
Most common cause of misfires on the 1.8T are the coils, but if you swapped coils and the misfire did not move with the coil, than it’s time to swap spark plugs and see if the misfire moves. Easy stuff first. When some people install coils they will smack the top of the coil to seat it in the well and end up cracking the porcelain on the plug. Sometimes you can see a black carbon line on the plug that looks like it was drawn on with a fine point sharpie. Always use the original Bosch or NGK R plugs!
If that doesn’t work, than remove, inspect, and swap injectors and see if the misfire moves.
If you really want to scope the injectors, you would backprobe across the two injector terminals. Probably one of the last things i would check. Your ECM is capable of recognizing an open circuit, short to neg, and short to B+ faults in each injector circuit and would store appropriate faults. Just listen to the injector with a hard handled screwdriver and that will tell you that the activation signal is OK.
When you say you swapped coils around, did you physically moved the COP from one cylinder to another ?
Next step, is to physically move the injector in question from one cylinder to another.
[quote=”theoldwizard1″ post=61806]When you say you swapped coils around, did you physically moved the COP from one cylinder to another ?
Next step, is to physically move the injector in question from one cylinder to another.[/quote]
Next step would be to swap plugs. Don’t omit the easy things.
By the way UKnewWho, do you have access to a VAG specific scan tool like Ross-Tech VAG-COM or VAS PC? You can monitor the misfires as they occur and give us more info on when they happen so we can isolate the issue as ignition, fuel or mechanical.
No kidding! How was that determined?
I recently had a 1.8 with collapsed lifters that would misfire on startup until oil pressure filled them up, and a 3.0 with a leaking head gasket that would seep coolant overnight and misfire when started up cold and log about 12 misfire events and store fault. Head gaskets very rarely fail on Audi and VW engines. I maybe see one every 2 years. I actually ended up replacing the entire bank 2 head on the 3.0 after i found some light pitting on the head.
[quote=”UKnewWho” post=61909]Turns out blown head gasket.
Thanks for the tips though.[/quote]
sorry to hear that. 🙁
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