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Discussion Starter · #1 ·
As above really, over the last two days my AGU 1.8T has developed an intermittant loss of power which is sort of like a missfire i guess, today it happened in 3rd gear between 3-4K revs but when i changed to 4th the engine pulled fine.

I had the ignition signal amplifier changed at the dealers last year after the car started running on 3 cylinders could this be related?

Any suggestions as to what it could be before I book my car into the garage?
 

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i bet it's the ignition amplifier!and i bet it's number 2 cylinder that is missing! ?87.00 from Euro Carparts,mate! the only other thing it could be is one of the coil packs.an easy way to tell would be to have the car running and remove each coil pack,one at a time, until the engine note doesn't drop any further.when you remove a coil and the engine note doesn't change(get worse), kill the engine,swap the coil with the one you suspect is faulty,start the car up,and if that cylinder still doesn't fire up,then it's a sure bet the amplifier has turned faulty! hope this helps!
 

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Discussion Starter · #4 ·
Cheers for the info mate, its only an occasional thing so do you think it could be the amplifier on the way out again?(i say again because the stealer charged me ?300 odd to change it last year when it went)

It hasnt done it today or yesterday evening whilst driving so will try your advice at the weekend.
 

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crazy thing is,the amplifier from Euro Carparts is the same part as from the stealers only it's a good ?200.00 cheaper then!!!!!
 

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Discussion Starter · #6 ·
Sounds about right though doesnt it [:p] i suppose the price i got was including the ?75/hr labour charge.

Is it a hard thing to fit then?

Also if it was replaced at the dealers last year should they not fix it for me for nothing if it turns out to be the same problem?
 

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Sounds about right though doesnt it [:p] i suppose the price i got was including the ?75/hr labour charge.

Is it a hard thing to fit then?

Also if it was replaced at the dealers last year should they not fix it for me for nothing if it turns out to be the same problem?
Dead easy. It unbolts from the back of the airbox, and has a plug at either end.

1. Clean all contacts on ign amp and do diagnostics as shown above.

2. If still no luck, take to stealers and ask for a replacement.

3. If no luck from them, try a scrappy or euro car parts as said above.
 

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Im Confused! (happens alot being blonde) but i dont get the removing the coil packs thing! Can someone elaborate a bit more for this dunce? Lol.

Cheers
 

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it's basically a 5 minute job to swap,max! i removed my amplifier from the airbox when i switched to a CAI and relocated the module on a stainless bracket,and used the heat sink from inside the airbox on the underside of the bracket to keep the module cooler.
 

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Im Confused! (happens alot being blonde) but i dont get the removing the coil packs thing! Can someone elaborate a bit more for this dunce? Lol.

Cheers
ok! here we go! IF you have a missfire,it's usually a coil pck,plug,or amplifier module. NOW! the first thing to establish,and easiest to check is the coil pack scenario. to do this.run the engine and one by one, remove the coilpack,and listen for a drop in engine revs.if you come across a drop in revs,you then know that the coilpack you have removed is working(hence the engine revs drop from the imbalance from losing a working coilpack). IF on the other hand you remove a coilpack and find the engine note DOES NOT change(ie. the revs drop), then you either have a coilpack problem,a sparkplug problem,or indeed, a amplifier module problem! HERE'S THE IMPORTANT PART! to establish whether it is a supply problem, (ie. not a spark plug problem), swap the coil pack you believe to be faulty with one that you know is good. if the problem moves with the coil pack swap, then you know it's a coil pack problem. IF the suspect cylinder is still faulty with a proven healthy coilpack, then that would suggest either an amplifier problem,or a sparkplug problem.swap the suspect plug with the one next to it, run the engine,and if the problem has not changed with the plug change, then it's an amplifier module problem. hope this helps!
 

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Discussion Starter · #11 ·
While we're in the process of answering silly questions how would you clean the ignition amplifier contacts?

Wire brush etc or switch cleaner spray?

Cheers
 

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Im Confused! (happens alot being blonde) but i dont get the removing the coil packs thing! Can someone elaborate a bit more for this dunce? Lol.

Cheers
ok! here we go! IF you have a missfire,it's usually a coil pck,plug,or amplifier module. NOW! the first thing to establish,and easiest to check is the coil pack scenario. to do this.run the engine and one by one, remove the coilpack,and listen for a drop in engine revs.if you come across a drop in revs,you then know that the coilpack you have removed is working(hence the engine revs drop from the imbalance from losing a working coilpack). IF on the other hand you remove a coilpack and find the engine note DOES NOT change(ie. the revs drop), then you either have a coilpack problem,a sparkplug problem,or indeed, a amplifier module problem! HERE'S THE IMPORTANT PART! to establish whether it is a supply problem, (ie. not a spark plug problem), swap the coil pack you believe to be faulty with one that you know is good. if the problem moves with the coil pack swap, then you know it's a coil pack problem. IF the suspect cylinder is still faulty with a proven healthy coilpack, then that would suggest either an amplifier problem,or a sparkplug problem.swap the suspect plug with the one next to it, run the engine,and if the problem has not changed with the plug change, then it's an amplifier module problem. hope this helps!
Wilko vt, when you say remove the coil pack do you mean completley take it out or can you just unplug it?
 

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I had this on my AGU 1.8T.

See my thread here...

http://uk-mkivs.net/forums/thread/19490.aspx

Mine has be absolutely fine since changing the coilpaks and int amp module. From memory you might need some heatsink compound when you mount the new amp module to the airbox. This is to aid heat transfer to the heatsink bit in the airbox.

I reckon the int amp module was faulty on mine. Oh BTW i thought new patrs have 2 year warranty from VW, so get -em to swap it...

Mine was so intermitant, if you disconnected the coilpak, then reconnected it it would be fine again!!

Also worth checking the wiring condition...
 

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While we're in the process of answering silly questions how would you clean the ignition amplifier contacts?

Wire brush etc or switch cleaner spray?

Cheers
Both, I used a bit of light emery/wet n dry and it's been fine ever since and this was near enough 18 months / 2 years ago. Check all the plugs have a secure connection too etc.
 

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it's basically a 5 minute job to swap,max! i removed my amplifier from the airbox when i switched to a CAI and relocated the module on a stainless bracket,and used the heat sink from inside the airbox on the underside of the bracket to keep the module cooler.
You couldn't take a pic or any info on your stainless bracket would be most useful ! [Y] I need to make something VERY similar.
 

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i'll see what i can do tomorrow.ok? and in response to the earlier question.you remove the coilpack from the spark plug and leave it on the top of the engine for a short time to see if the engine revs drop.if they do,it would signify that what you have just disconnected has made the engine run on 1 less cylinder,meaning that that plug, and coil pack, are fine.
 

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Discussion Starter · #17 ·
In true lazy fashion i havent got round to this yet and now my car is running really badly so this weekend is the time to do it.

But looking at this pic http://uk-mkivs.net/photos/ctp/picture626197.aspx from ctp.s maf thread the bit i thought was the ignition amplifier appears to be the maf sensor, so can somebody either point to the ignition amp on this pic or post one with a big dumb arrow on to help me out. [Y]

Cheers
 

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That is definitely the MAF in that picture. I can't see an ignition amplifier in that picture but maybe diesel doesn't have one. The ignition amp is a box maybe the size of a pack of cigarettes and it's screwed directly to the side wall of the airbox. It's on the side of the airbox that faces the windscreen.

Edit: here's a pic of an Audi one: http://uk-mkivs.net/forums/thread/511097.aspx
 

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Discussion Starter · #19 ·
That is definitely the MAF in that picture. I can't see an ignition amplifier in that picture but maybe diesel doesn't have one. The ignition amp is a box maybe the size of a pack of cigarettes and it's screwed directly to the side wall of the airbox. It's on the side of the airbox that faces the windscreen.

Edit: here's a pic of an Audi one: http://uk-mkivs.net/forums/thread/511097.aspx
Cheers mate thats a great help, i will give this a go on saturday, will try and clean the maf and the airfilter if the stuff comes in time [:D]
 

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i'll see what i can do tomorrow.ok? and in response to the earlier question.you remove the coilpack from the spark plug and leave it on the top of the engine for a short time to see if the engine revs drop.if they do,it would signify that what you have just disconnected has made the engine run on 1 less cylinder,meaning that that plug, and coil pack, are fine.
Coincidentally the same is happening to my car [1.8 T AGU, 1999] at the moment and occurs intermittently. However I find this normally happens when the engine is cold and what frightens me is the engine movement, its all over the show! Has anyone else experienced this? My steering wheel also shakes when this happens.

I found that if the car had been running for 10 mins then switching the engine off and back on cured it sometimes.

Anyhow I took it to my mates garage and carried out the coil pack / spark plug test as mentioned by wilko vt. We found that cyclinder 3 had no impact on the engine when removing the coil pack, whereas all the other cylinders did. Placing a working coil pack into cyclinder 3 did not fix the problem either. We put a brand new spark plug in cylinder 3 and still the problem occurs. At this point I was thinking this is going to be expensive.....

I guess my next step is to check and clean all connectors, failing that looks like its going to be a new ignition amplifier!
 
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