Jump to content

Recommended Posts

my car is running really lumpy in the low rev range, worse when it warmed up. i have changed the plugs leads, vagcom the car said collant temp switch was intermitant and air flow sensor was intermitant . changed them both still no change although faults have not come back on vagcom. i have removed the coilpack to inspect no visable signs of any cracks and looks in good condition. i am running out of ideas as to what it could be. car was running bad before plug and lead change so thought it was that.. any sugestions as to what else to look into would be helpfull.... :-(

Link to post
Share on other sites

Okay, a couple of thoughts:

There are two coolant temp sensors, which did you replace (four wire yellow or two wire blue)?

Whe my vr started to behave like yours I found it was the coilpack (even though it had no cracks at all and appeared to be in good condition). Coilpacks fail in one of two ways:

1. cracks form and allow arcing to occur.

2. the coil itself within the back breaks down and it's output impedance under load increases. This give a weak spark but no external sign of damage.

My problem was number 2. Sadly, I was not able to find any test that would allow me to measure a problem with it off the car (I tried all the impedance related tests that I found on the web and in the bentley manual etc) but replacing the coil fixed the car a wee treat.

Coilpacks are a git to diagnose as the only real way to be sure is to try a different one. If you know someone locally with a VR then maybe you could borrow theirs for an hour to try it out?

Alt, there are a few cars being broken on the forum rigth now so maybe you cna pick up a bargain coil from one of those?

Cheers,

ip

Link to post
Share on other sites
×
×
  • Create New...