markkl

I just purchased a low mile (86K) 89 200 tq and have a problem with cold and hot starts. It cranks very long before starting. (30 plus seconds) I am in the process of troubleshooting fuel system related items (check valve, fuel regulator, etc...). Could it be anything else?? Thanks for any help.

Will Ng

Congrats on your find, that is low!

Cold start>
The fuel pump relay should run the pump for 2 sec. in the 'ON' position to prime the system to pressure when starting the car. Make sure this is happening.

Another common cause is the CIS's mechanical fuel injectors are leaking due to age.
Usually this is accompanied by a strong smell of raw fuel upon cold start up.

Hot start>
On top of those listed above....
The 200q has two after-run cooling systems.

One is for cooling the turbo bearings and prevent oil coking by using an auxiliary electric water pump. This turns on and switches on the radiator fan at its low-speed setting when it detects high coolant temps.

The other is a fuel injector cooling fan. The one flaw of the Audi I-5 is that the intake and exhaust ports are on the same side. This requires the injectors to also be situated there.
The turbo-ed I-5's increased heat has caused vapor lock in the fuel system after a hot run.
If high under hood temps are reached, a squirrel cage fan blows cooling air at the injectors and above the valve cover to prevent vapor lock.
Make sure your system is working. The sensor is at the rear of the intake manifold, which activates a timed relay.

HTH.
Will
1990 200tq
"the pentosin sprinkler"

markkl

After checking fuel etc..., I have found that the issue is a no spark at all.

I am trying to find the source of my problem. Is this a common failure?? ... Cranks over fine,
but no spark at the plugs or from the coil, but 12v at the coil?? Timing belt is okay... According to SJM, I checked for voltage at the ECU, no voltage at pin 35 which should be 12v.....Checked grounds, all good ... Any ideas??