16 valve holding back

[crimp]

car broke down last week,I thought it was the pick up pump so replaced it. Since then its been going great until you hit about 4000 revs when it would not rev any more. Any way I've put in a new coil and it seems OK , revving up to the red line. but have not been able to get it on to a fast bit of road yet. Does any one know what happen's when a coil is on its way out thanks.

[Overseer]

when the coil in my mk3 valver was on its way out the car would judder and lose power sometimes.

i eventually broke down.. it just lost power, picked up power.. lost power... and never got it back.. so I got stranded and had to get towed home.

[Gambit]

sounds like the timing is out

can redline in neutral but when under load (in gear) it cant??

[tinman]

The coil breaking down can make many things go wrong. Bad timing, stalling, you name it - the coil can cause it. Considering they only cost 20quid or so, they are more or a consumable than long living part.

If you still have troubles check the timing crystal.

In the engine bay, right under the drivers side wiper on the shelf under the windscreen is the timing crystal. If the timing crystal is shagged you will lose high end timing on the ignition.

If you have a 16v do not buy a non VAG part. The 16v part is different despite what GSF and ECP will tell you. You could always try and get the part of a smashed 16v of course.

Tin

[tinman]

i forgot to say, sometimes the timing crystal (not sure of its real name) is breaking down yet you wont notice it, so buying a new one isn't such a waste as you may think.

you'd need an osciliscope to identify that it was breaking down though.

if i remember correctly, the best company who ever tuned up my 16v was the local krypton tune guy. he charged a fraction of main dealers but still serviced the car and retuned it. the car was always awesome afterwards. exactly how a service should be.

[Veedubgt18v]

i think they are called the t-hci switch or something like that? its not very big and is attached to a big piece of metal plate

[tinman]

yeah, think thats the chappy. booger to get off the car without breaking it though...

[crimp]

Just tried it out under load , and is missfiring at about 6500 revs, is that the rev limiter cuting in or that timing thing that I've never heard of before. I changed the cam belt a while ago and thought I got it right as up to 6500 revs the car feels great.

[VeeDubGTI16v]

nah the rev limiter is 7,100 i think

have you seen if the throttle cable is tight enough? maybe its not quite opening enough

[tinman]

rev limiter comes in at 7.3k and the limiter is absolutely vicous dropping you to 5.5k if you do it in gear.

if it is mistiming at 6.5k i would put my money on the crystal starting to fail. however, the best way of testing it is to use one from a friends GTI first. you may notice that the more you hit the limit, that over a few days it may well start dropping down the rev scale.

be very very gentle when removing the unit containing the crystal. if it breaks - you are totally screwed.

and make sure you eventually use a VAG part if it is that. the non VAG parts are utter sh!te. they may work on 8v GTI, they don't on 16vs. However, the VAG part works on both. Which I found a bit odd.