2.8 12V runs like sh;t

[ThatGUY]

My 2.8 90 doesn't run for beans. It feels low on power and when at WOT it shakes a little before it goes. When i let off the throttle at any time after about 20-40 seconds the car almost dies, most of the time is catches it self. Yesterday when I was driving around 70mph on the motor way the car would cough like it would cut out for a second.


I have replaced the fuel filter a week ago.
Tested the resistance all six injectors- ok.
Cleaned MAF and ISV recently.

I keep thinking it’s a fuel problem but why would it act up erratically
Any thoughts would be greatly appreciated

Andrew

[BeckyA4]

Coil packs fail and also suffer from plug leads breaking down. Any fault codes on that?? You can get them the same way as the S2.

HTH

[ThatGUY]

I don't have a scan tool to get any codes. Tomorrow I'm going to try and test the coil.

Thanx
Andrew

[horvathg]

My 2,8 V6 coupe quattro does almost the same. At the end it goes some 235 km/h but alwasy seems there is some level of fuel starvation. No reason my garage could find.

[dan_b]

Sounds rather like the problem Honahon had, which was eventually discovered to be coilpacks.

[ThatGUY]

I tested the coil pack according to the Bentley and they are fine. Would they still be able to act up tho? I also changed my spark plugs... they weren’t that old but when I pulled them out they had heavy deposits on them. I doubt these solved the problem it may have weakened it... damn car.

Thanx for the info
Andrew

[audiman]

Fuel pressure OK??

[ThatGUY]

I thought about that too. I was told that an electric fuel pump wouldn't act up it either works or doesn't. Could the fuel pressure reg go bad?

Andrew

[audiman]

How about if something was floating around in the tank?? Like a leaf or something stupid? Have come across that before, where it partially blocked the pump pick up.

[monkeyboy]

I don't know what it could be, just thought i'd say hi.

[horvathg]

Fuel filter?

[ThatGUY]

Thanx Monkey... here is a Banana.


I replaced the fuel filter about a week ago. The new plugs did alleviate the coughing while driving but it still idles poopie.

Thanx Guys
Andrew

[audiman]

How are the compressions? I have also heard of valves burning out on some of the V6 lumps

[ThatGUY]

Ooo, when the engine isn't fully warm at WOT there is a rattle that sounds like a lifter, maybe they are linked. Its worth a check.

Does anyone know if a FPR can go bad or get cloged?

Thanx
Andrew

[audiman]

Very very rare for an FPR to fail.