The Sciricco ('84, 8V) is pouring out white smoke. I ran a compression test and all the cylinders came out around 180 psi. The exhaust smells strongly of gas like I have a headache after the car running for maybe 5 minutes. The plugs are BLACK.
Any idea of where to go from here? Stuck injector? Something else?
Check the fuel pressure. Stuck injector, you'll see it. If not, move on.
EFI or K-jet? Sounds awfully rich to me. If EFI, check temp sensors and fuel pressure. If Kjet, make sure the electrical heater in the warmup regulator is working correctly.
Being an 84, it should be a CIS lambda car. As such, you should only be running that rich if the cold start injector is stuck on, or if the o2 sensor is bad. I had the O2 go bad in my '88 GTI (CIS-E) and it dumped a ton of gas into the engine.
I don't know if you have it on a CIS engine, but check to see if you have a coolant temp sensor. Lower resistance means the coolant is warmer.
Being an 84, it should be a CIS lambda car. As such, you should only be running that rich if the cold start injector is stuck on, or if the o2 sensor is bad. I had the O2 go bad in my '88 GTI (CIS-E) and it dumped a ton of gas into the engine.
On second thought, you might have a coolant temp sensor since there must be some sort of computer to interpret the o2 sensor signal. Lower resistance should correspond to warmer sensor temp.
Brotus7 wrote: On second thought, you might have a coolant temp sensor since there must be some sort of computer to interpret the o2 sensor signal. Lower resistance should correspond to warmer sensor temp.
Which one? There is one for the gauge and one for the light.
Either way what would that the coolant temp sensor tell me about the running rich.
It is a CIS car.
Fuel pressure, bad cold start injector, bad thermo time switch, bad auxilary air valve, dirty warm up regulator, bad o2 sensor or Lambda valve causing car to stay in open loop. I'd also check the fuel distributor pin and the air flow flap for smooth movement. This is just off the top of my head of things to check and not necessarily in that order.
Guess that's the down side of not having OBDII...
chrispy wrote: I'd also check the fuel distributor pin and the air flow flap for smooth movement.
Where are these located?
Also check electrical connections and clean if necessary. Bad connections can cause all of the above and more...
The metering pin is located under the fuel distributor. If the car is running ok, other than rich, its probably fine but if it sticks there could be an increase in fuel flow. The airflow flap is located under the fuel distributor in the air box. Its the flap's movement that controls the pin's movement in the fuel distributor and it can get gummed up and stick too. Like I said, if the car is running fine, other than rich, I'd look more at the cold start circuit of the fuel system than fuel delivery.
So I was reading my Clymer manual and for running rich, it suggested checking CO adjustment, check the control pressure regulator or wiring, defective cold start system.
My problem is for the fuel pressure test, the tester needs to be in between the fuel distributor and the control pressure regulator. None of the fuel pressure testers that the auto parts stores carry seem like they would work. The manual calls for a VW tool P378.
Anyone know where I can find a replacement for this tool?
Most fuel pressure test kits say they will not work with K-jet. There is supposed to be a "T" valve to do it correctly.
If you can beg borrow or steal a copy of this old and rare book it has all the info you need to DIY your own tester
Sadly it is hard to find and expensive. I should still have a few copies somewhere. I will try and look for them and see if I can take pics of the pertinent info.
In reply to ditchdigger:
That would be greatly appreciated.
In the mean time, are there any good VW forums to go look at?
Don't limit yourself to vw forums. Volvo, Mercedes, Porsche and others used that same system. Googling CIS pressure tester popped up a few good threads at pelican parts.
93EXCivic wrote:Brotus7 wrote: On second thought, you might have a coolant temp sensor since there must be some sort of computer to interpret the o2 sensor signal. Lower resistance should correspond to warmer sensor temp.Which one? There is one for the gauge and one for the light. Either way what would that the coolant temp sensor tell me about the running rich.
Neither. The sensor you're looking for is the sensor for the ECU, not the sender for the warning light or gauge. I believe it's the sensor on the bottom of the housing that the upper radiator hose connects to, and the plug should be brown. If that sensor is bad it will not tell the computer that the engine is warmed up, and continue to dump fuel like the engine is cold.
I doubt it's a fuel pressure issue. The CIS systems run around 80psi normally, so it's almost impossible for them to have too much fuel pressure. Generally you need to check fuel pressures if you've got a lean or no start condition.
A rich condition on those cars usually ends up being a bad CTS, bad O2 sensor, or bad ECU.
Actually, now that I think of it, I was thinking of CIS-E. I don't think CIS has a CTS. But it does have a thermo-time switch that controls the cold start valve, and both of those could cause a rich condition. The frequency valve controls fuel via O2 sensor input to the ecu, which can also cause a rich condition.
Try unplugging the cold start injector. If that "fixed" it, then it's probably a bad thermo-time switch. If it didn't, with the engine warmed up unbolt the cold start injector and block the hole in the intake and start it. If anything comes out of the injector with it unplugged, it's stuck open.
If that didn't change anything, try unplugging the frequency valve. IF that fixed it then you've probably got a bad O2 sensor or bad ECU. It's possible that the frequency valve could be stuck too, but I've never seen that happen.
I seem to recall the Harbor Freight master fuel pressure test kit ( the big one) includes fittings for Bosch fuel injection. I've seen old school CIS test kits on eBay. If you go to the Bimmerforums.com E21 section there is a DIY thread stickied that includes CIS troubleshooting and a DIY fuel pressure gauge. After I sold my E21, I used that forum for troubleshooting my MK2 Golf's CIS issues. The Vortex 8v and CIS tech forums are tolerable, and likey there is already an answer there.
http://www.harborfreight.com/master-fuel-injection-pressure-test-kit-97706.html
chrispy wrote: I seem to recall the Harbor Freight master fuel pressure test kit ( the big one) includes fittings for Bosch fuel injection
I'll be damned. It does!
This cheap one will not work though
http://www.harborfreight.com/fuel-injection-pump-tester-92699.html
Make sure the flapper on the fuel distributor isn't stuck UP, it has happened to me more than once.
The cold start injector I have never seen misbehave, but unplugging it is easy.
Did you do/change anything recently, or is this a "ran when parked" type project?
Paul_VR6 wrote: Did you do/change anything recently, or is this a "ran when parked" type project?
It was running fine after the last autocross and went to start it to move it so I could pull something else into the garage and it was running rich and smoking.
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