Car Was Idling A Bit Rich Then Just Died!

[Daboss]

Have not posted in awhile because car was off road waiting for a dump pipe install, but still passed through to read the topics. Whats up everyone? I am having a little situation and all the expert advice, theories and suggestions are welcome. Here goes.

My car was awaiting a dump pipe install after a rebuild so it was off the road I started it every other day just to keep it in order and make sure it ran. Now when running it would sometimes smoke a little which I assumed was just a bit of oil burning off from the freshly installed journal bearing turbo. It went away after awhile anyway. The car was running pretty rich as I would smell gas as the car was running, but no way to tell as the dump wasn't installed so no wideband or normal O2 sensor.

On Sunday i decided to change the number six spark plug as it was missing on that cylinder. I did, noticed that plug was covered in carbon and miss went away after new plug installed. Now I did my every other day routine of letting it run to operating temp but this time there was that subtle miss you get when the plugs are gapped to tight, I paid no mind to it and continued to let it run. I could smell the car was running rich so decided to lean the tune out at idle to see if that would help, No matter how much I leaned it out, which was only maybe 10 down presses on the pfc it didn't really stop the rich smell.........so I put it back to normal. Car ran this way for about 10 to 15 mins.Cut the car off, went out came back and decided to run it again. As it started it ran for about 20 secs did the little pops and then just died. Tried to restart the car and nothing, it would roll over but not start, could smell gas vapors with every attempt to start.

Tried a few more times with no luck so decided to do some test in short everything is ok except the car will not start. Timing is good, have fuel, spark and compression on each cylinder is 120 psi. But car will not start and when removing the plugs they are soaked with gas and with every attempt to start, gas is smelled very strongly.

What do you guys think it can be??? If the valves are burnt will it stop the car from starting? All help appreciated, Thanks.

[GTRPowa]

After a turbo install mine idled fine, got rich, started a splutter, died on the road, would not restart. Would start the next day but only for a few seconds. Then dies everytime, etc.

For me it was the CAS sensor. From what I remember is has triggers for both ignition and fuel. Replacing CAS with a mates and didn't fix, but after some muddling around it came down to a bad connection in the plug. Some contact cleaner, my old CAS back in, and she's run fine ever since.

I never would have originally blamed the CAS because I figured if CAS was dead, car would never have started at all. How it turned into a very gradual misfire and an eventual engine death is beyond me. Check your PFC when you crank the car, you should see the revs at like 160-200 rpm or so. If it stays at 0RPM during crank, it's most possibly your CAS, or related connections.

Good luck.

[DVS JEZ]

Put a new set of plugs in it. Chances are they will all be fouled up.

Get ur inj, tested.

Put a wideband on and set idle AFR.

And try to avoid excessive idling of the motor

[dorifticon]

I had similar symptoms once on my z32 300zx.

Turned out it was the water temp sensor. More accurately, the wiring going to the send (immediately before the plug). Of course, not the gauge sender, the actual ECU temp sender.

It had corroded out and wasn't getting any connectivity, so the car always thought it was in cold start mode.

Ran like absolute s--t, then cut out corroded section reattached to plug and was all good.

[chocco]

Sounds like the problem I ran into.

Car was running fine then started to run grumpy then bad and then backfired once and died.

Couldnt start it as it would only just kick over, unplug the CAS and it would kick over alot easier

then with it plugged in. Swapped the CAS for another and away it went.

[Daboss]

I tried another CAS, I have a spare, with no luck will have to find another just in case the two are bad. Will have to look at the water temp sensor wires and get a new set of plugs. Will do the checks mentioned and let you guys know how it goes. Tanks for all the suggestions keep emm coming.

[Craved]

Running the car with no dump pipe? have you checked the wiring behind the turbo for melting?

[simpletool]

Leaking injector ?

[JKR-32]

I had similar symptoms once on my z32 300zx.

Turned out it was the water temp sensor. More accurately, the wiring going to the send (immediately before the plug). Of course, not the gauge sender, the actual ECU temp sender.

It had corroded out and wasn't getting any connectivity, so the car always thought it was in cold start mode.

Ran like absolute s--t, then cut out corroded section reattached to plug and was all good.

Water temp sensor?

Engine out?

[Daboss]

Running the car with no dump pipe? have you checked the wiring behind the turbo for melting?

No will do that also, good thinking did not even think of that.

Leaking injector ?

Changed injectors, fuel still soaked the spark plugs and scent was very strong in the air.

[Daboss]

Okay here is an update bought six new plugs, installed them and same outcome car will crank but will not start also after trying to start inspected plugs and they were soaked with fuel. Checked wires behind turbo exhaust they are fine, checked water temp sensors, they are both good the one in the radiator and the next one in the manifold. Checked both CAS on another car and they both started the other car. Checked fuel, spark and fuel pressure all are present. I am about to throw in the towel cause this is way past my knowledge on this car, I have tried everything suggested and what I can think of and nothing works. I am stumped. Went from running, to a slight misfire at idle to not starting at all. Are there any other suggestions cause right now the obvious isn't the problem, so whatever idea you have throw it out there see if you can help me get my car started.

Checked all sensors on pfc and everything is good, changed injectors still no luck. HELP!!!!!!!!!!!!!!!!!!!!!!!!!!

Edited May 18, 2011 by Daboss

[Craved]

AFM plug? AFM itself?

how did you check the spark?

adjustable exh cam gear?

swap ignitor? if early 95 with s1 ecu

[tridentt150v]

What about fuel??? how long exactly has it been 'sitting around'??? Maybe your fuel is off???

[Daboss]

AFM plug? AFM itself?

how did you check the spark?

adjustable exh cam gear?

swap ignitor? if early 95 with s1 ecu

Well according to the pfc voltage is present to all the sensors that need them guess I will have to see if I can find someone to swap a z32 afm, have series 2 so no ignitor and checked spark by grounding spark plugs and spinning CAS. No adjustable cam gear.

What about fuel??? how long exactly has it been 'sitting around'??? Maybe your fuel is off???

That same gas was sitting in the car for at least eight months or so. So even though it started and ran the car previously that same batch of gas could also be the cause of it not starting?

[Rolls]

Get a consult cable and check for any other faults.

[Room42]

Maybe you got the afm wrong setting by accident. I did that once. The pfc changes the setting just by going to the afm part and going down and then going back out. Try going to the afm screen and go up to the standard r33 and then go back.

[DVS JEZ]

Thats a very good point. Something simple but very easy to do.

[Daboss]

Maybe you got the afm wrong setting by accident. I did that once. The pfc changes the setting just by going to the afm part and going down and then going back out. Try going to the afm screen and go up to the standard r33 and then go back.

Ok will take a look. It is worth a shot. Running a z32 by the way.

Here is an update, got a new set of plugs, added two gallons of fresh gas with a gallon of xylene and a bottle of fuel injector cleaner. Car still will not start. Took out fuel rail with injectors installed primed system and noticed number six was leaking, changed that for another injector made sure that one was not leaking along with the other five. All were sealed properly and fired when cranking the car. I also took out the coil packs and cranked the car and observed all the spark plugs firing. Mistakenly pulled out injector while the rail had fuel in it and was attached to plenum so number six was filled with fuel, while the spark plug was out i cranked system to get rid of excess fuel in number six cylinder and left open to air for awhile. Fitted plugs and cranked system without injectors and when I removed the plugs, 1&2 were dry 3,4,5,6 were wet assumed it was fuel from previous cranking and proceeded to dry all cylinders, by cranking system with no plugs attached and leaving all cylinders open to air. Was in the process of testing the plugs again to see if they got wet with fuel while the injectors were unplugged, but the battery died so have it charging now and will proceed tomorrow and let you guys know how it goes.

[Daboss]

UPDATE!!!!!!!!!!!!!!!!!!!!!!!!!!! Checked afm on pfc and it was at right setting, set for vg30 which I have installed.

Ok so I fully charged the battery overnight and continued with my troubleshooting. Removed fuel rail and disconnected injector harness and proceeded to check if any leaks or if injectors were firing somehow with harness disconnected. Everything fine with injectors. Now decided to take a look at spark plugs to see if wet, cause there should be noway they would be wet as rail was disconnected. 1&2 were dry 6 was suspect could not really tell while 3,4 & 5 were wet as......decided to clean them off and try again. This time all were dry except 4 & 5. Took all out gave engine a few cranks to see if I could get rid of excess gas then replaced plugs and cranked again. Again 4 & 5 were wet so decided to leave them out so gas can have a chance to vaporize and come on here to report my findings. So what do you guys think???????

Cause as of now the only thing I haven't done is check the cams to see if they are broken and that's it. I am tired as and bummed out cant think of anything else. Ready to throw in the towel on my baby !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Edited May 21, 2011 by Daboss

[DVS JEZ]

Check spark again. See how strong it is.

Do a compression test.

Check the cam timing and cas timing.

Check with timing light while cranking and see if it lines up with the crank pulley marks