help, im in cis hell!!! please

[jason2guy]

ok, car will start and wont idle. starts everytime just wont stay running and if i give it gas it will backfire.
all started when i got off the freeway, the car died but started back up and i was able to limp home.

new cdi, coil, green wire mod, cap, rotor, plugs, wires in spec.
just checked for a spark at the coil lead. healthy spark.

im thinking the cold start valve gives it that initial juice and then
maybe a clogged fuel line?

tell me what to do

[Tyson Schmidt]

Take off the airbox lid and check that the pop-off valve is still there. Sometimes they break out of their epoxy from a good backfire, and cause a massive vacuum leak.

[jason2guy]

i dont have a pop off, call me crazy. and i did the lift the air sensor plate test and went one further and checked for fuel at an injector site and it was there, flowing out while lifting the plate.

i just checked the 02 relay. the fuse is good but not sure about the relay

[jason2guy]

could my air box be cracked? OMG

[jason2guy]

you gotta point there.

im thinking a fuel line is clogged, but where?

[Carl_Boehme]

If the line is plugged it is most likely at the filter. Make sure the AAV is operating. If it isn't then the cold engine won't idle. (Cold engine is a heavier load than a warm engine and the AAV needs to be partially open).

Install the pop off ASAP.

Carl

[cantdrv55]

Does your car start now and idle since it's been sitting? If not, can you press on the gas pedal lightly and get it to stay on and idle? If so, readjust your idle speed up. Something similar happened to my car recently. I thought it was something serious but it just turned out to be low idle speed. After fiddling with the adjustment a few times, my car's running great again.

If you can't get it to start at all but you've got fuel at the injectors, then I think you've ruled out the filter, pump, etc. The injectors are the end of the line, I think. I'm a weekend wrench so take my advice with a grain of salt.

[Porsche_monkey]

Starting but not idling is a classic 'too lean on start-up' symptom. You get started with the cold start injector but after the starter shuts off your mixture is too lean to run or take any throttle. You need to check your fuel pressures. WUR, or massive air leak is my guess, maybe a vacuum hose fell off? Can you keep the car running by moving the air flapper manually

[Paulporsche]

What everyone else said, plus:

You may be slightly lean in general. Try richening a little.
Raise idle speed a little to counteract richening, then a little more.
Look for air leaks in hoses and CIS components
AAV or AAR
WUR
DME or 02 sensor
Oil filler and Gas Caps

Good luck and let us know.

Paul

[Porsche_monkey]

You can find a vacuum leak with an unlit propane or acetylene torch.

[vash]

i bet your mixture is way lean. get the pop off valve, you are a disaster waiting to happen. strangly enough, my car did the exact thing. i even blew my pop off valve out of the epoxied hole. i ended up, taking the car to the mechanic to have them adjust my mixture which cleared the problem. funny thing, i think the title of my thread asking for help was very similar to yours.

[jason2guy]

yup, i ordered the cis kit from jc whitney. so well now tomorrow what is up.

im thinking the control pressure is too high right from start up making it starve for fuel, just a hunch.

[vash]

yay! the qauges can be very informative. do you have any CIS book?

[Porsche_monkey]

http://www.phat-gti.com/downloads/boschtech-12d.pdf


Try this.

[jason2guy]

yup got that. but im not a rocket scientist

i have some good stuff on cis. ill fix it. or itll stay broken in my garage
forever!!!!!!!!!!!!!!!!

[AFJuvat]

Had one similar a few months back - it was a combination of a bad warm-up regulator and bad O-rings in the pressure regulator in the fuel distributor

The biggest symptom that one had is the car kept leaning itself out - no vacuum leaks.

AFJuvat

[Lorenfb]

"all started when i got off the freeway, the car died but started back up and i was able to limp home."

Focus your diagnostics here. Check out what could have happened as the car
came to a stop.

As many have said, the fuel mixture is too lean causing the backfire & running problem.
Check out what could have happened to cause the mixture to go lean.

It's unlikely that;

1. The WUR has just allowed the control pressure to increase. They don't fail this way.
2. The fuel distributor has failed. This is very rare as fuel distributors are very reliable.

Possiblities:

1. intake air leak
2. fuel pump pressure (system pressure) has dropped
3. restricted fuel line/filter/accumulator

Try lifting the sensor plate as someone cranks. This will richen the mixture and
may allow the engine to run.

Obviously the best approach is to; backtrack problem occurrence, check control
and system pressures, & check for intake air leaks, e.g. bad/misaligned air boot.

[jason2guy]

wouldnt it be ridiculous if after all the BS its a clogged fuel filter.
which is about 1 mo old BTW.

i should probably check that.