8V ITB car runs like C***

[Camaro631]

We are running a 1985-6 VW golf 1.8 V in ITB, . Yesterday at Road America, the car started out running strange (down on power) then all of a sudden in the front strait the it ran, OK, then it would sputter in the corners but cleaned out in the straights, This morning put in Bosch 4310 Plugs ( the standard heat range) , it appeared to run but still missed, then after sitting would not even run enough to get the car moving.. It sputters feels like a missfire and will not build RPM (like running rich). Would barley make it on the trailer If we bump timing to like 20- 30 degrees it gets better.

With CIS injection, stock ignition,

Timing belt is tight and appeard not to have "slipped a tooth". Replaced plugs, wires, cap rotor, knock sensor, coil, igintion module, ( complete distributor) all this was swapped from a running car.

Did we go the wrong route and its fuel?



JimTripleHelixRacing

[zracre]

I am far from an expert on cis and cis-e but it sounds like a fuel problem... you need to check the control pressures. Quick check: take an injector out and tap it on something solid to see if there is anything stuck in them...I had a fuel distributor/lines go bad and come apart in little black bits.

[JamesB]

So it was running great in the straight line but like crap in the corners. Check your grounds and check your lead wires. Since August I had a oddball missfire in the exit of high G left hand turns (3 and 7 at summit point.) I thought it was fuel but everything checked out on that. Then I found a loose ground and fixed that.

Well Saturday afternoone I came out of 7 agian and the car was really breaking up as I head up from 8 and all the sudden I had some smoke. I knew it was electrical so I threw her in nutral and hit the battery cutoff and coasted into the pit in and got to black flag. The smoke went out as soon as I killed the battery so I had to figure out what happen.

It turned out the heat from my header had made the O2 sensor heater wire insulation pliable and since it wasnt completly zip tied tight in high G left handers it was touching my hard brake line. Well after a while I guess the insulation wore away and it was actually shorting out, it just took the right time for it to get stuck on the fuel line and cause an issue.

So go over your engine harness and grounds and look for anything like that.

[racer_tim]

Change the fuel filter. Check for "chunks" in the injectors, like zracre said, and also check the fuel pump for "chunks".

[Camaro631]

Injectors are clean, and mist well. lines are clear, 2 upper o rings are bad.. will have them Wednesday. Working on Fuel filter in the morning

I will keep you posted

[Camaro631]

it looks like 2 of the upper o rings for the injectors were bad.. appears to be running now