1995 850 Starts Fine, weak Restart. MVSOLVED FIJ

[DoriDori]

Yes, his test should still work. There's a vacuum line to the FPR right between the 2nd and 3rd (or is it 1-2?) cylinders on the fuel rail. Disconnect it and see if it's wet or smells strongly of gas.

Aside from that being the culprit, maybe you can help us narrow it down. If you can get it to where it won't start next time, can you:

-Check for (strong) spark by disconnecting a spark plug/distribtuor wire and grounding it to the top of the head (thinking being cam/crank sensor)?
-Depress fuel schrader valve briefly until it spurts a little bit of fuel (vapor lock?)
-Unhook line to purge valve @ intake manifold.

Here's an update:

Got the condition to occur.
-Pressure sprays out the fuel rail when pump is non. (key to position ignition)
-Sent 12v to the EVAP purge valve with car off, cold, and it opens.closes

Perhaps I didn't mention this but if you drive the car until its up to normal op temp, then turn it off, then immediately turn the car back on it will start just fine! It's only when the car has sat for between 10min-30min. After that interval it starts no problem. Strange!!! I have a used Bosch CPS in the mail.

EDIT: picking up new today:plugs, wires, coolant sensor, thermostat 180.

[DoriDori]

Update after new parts installed:

Just installed New wires, Plugs NGK gapped to .028, Thermostat 180 (Ga heat wave approved), New coolant temp sensor under the thermostat.

Drove 30 miles in 90 degree heat to work, ran like a champ too. I get to work, let it sit 10 min and STILL NO START!!!! MY GOSH!! This is getting insane. Only thing left to replace as far as spark goes is the cam position sensor and the crank angle sensor.

Any help much appreciated.

[jblackburn]

Update after new parts installed:

Just installed New wires, Plugs NGK gapped to .028, Thermostat 180 (Ga heat wave approved), New coolant temp sensor under the thermostat.

Drove 30 miles in 90 degree heat to work, ran like a champ too. I get to work, let it sit 10 min and STILL NO START!!!! MY GOSH!! This is getting insane. Only thing left to replace as far as spark goes is the cam position sensor and the crank angle sensor.

Any help much appreciated.

Yes, since we seem to have eliminated fuel problems, my bet would be on one of those two, but I'm not sure which.

I do wonder if it might be because the injectors aren't pulsing though. IF you crank over and over for a while without a start, can you pull out a spark plug and sniff for fresh fuel? Should be pungent if it isn't firing, and if there's no raw fuel smell, it's a good bet the injectors aren't firing.

This will help you isolate cam (fuel) vs crank sensor (spark).

[DoriDori]

Update after new parts installed:

Just installed New wires, Plugs NGK gapped to .028, Thermostat 180 (Ga heat wave approved), New coolant temp sensor under the thermostat.

Drove 30 miles in 90 degree heat to work, ran like a champ too. I get to work, let it sit 10 min and STILL NO START!!!! MY GOSH!! This is getting insane. Only thing left to replace as far as spark goes is the cam position sensor and the crank angle sensor.

Any help much appreciated.

Yes, since we seem to have eliminated fuel problems, my bet would be on one of those two, but I'm not sure which.

I do wonder if it might be because the injectors aren't pulsing though. IF you crank over and over for a while without a start, can you pull out a spark plug and sniff for fresh fuel? Should be pungent if it isn't firing, and if there's no raw fuel smell, it's a good bet the injectors aren't firing.

This will help you isolate cam (fuel) vs crank sensor (spark).

Cars for sure getting fuel: can smell unburnt fumes while attempting to start. Again, after conditions are met it will always start after about 5-10 cranking attempts. Today I replaced the crank angle sensor. Problem still there thou!

[osman]

Fuel injector relay, underneath the radiator fan shroud next to the fan speed relay.

[Pebsi]

Very interested in this thread as I have EXACTLY the same issue with my 95 T-5R, so far changed:
Fuel pump
Coil,
Fuel pressure regulator (under fuel rail)
Idle control valve
CAM position sensor is fairly new anyway

Good point raised about it being a heat soak issue. Wondering if it could be heat soak affecting either the Fuel pump relay (although I hear it priming) or the Fuel Injector Relay which if mounted in front of the engine will only ever heat up when the car is hot and stationary.

Going to try that next. Need to solve this too as it's a PITA and really peeing me off.

If you solve it, please please please update the thread and I'll do the same. Mines not a daily driver might take a while before I report back on my findings

[abscate]

Did we rule our FPR for these guys? I don't see that upthread.

[Pebsi]

The FPR was the last thing I changed and problem still persists. Interestingly it was cheaper to have one shipped from the US to the UK then to source one in the UK.

As it obviously affects a Turbo and non Turbo it must be a part common to both.

Forgot to mention I have changed the coolant temp sensor too.

Really frustrating.

[Pebsi]

Guy's
When I changed the FPR I noticed one of the fuel injectors looked a lot more ragged then the other 4. I cleaned it up and reinstalled it.
If it is leaking when hot it could flood the engine (just read this on another thread).
Another thing is that when it does eventually start it's not what I would call a clean start. Its more of a chug before it smooths out (Fractions of a second but definitely different to a cold start). Difficult to explain but could well be consistent with clearing a flooded cylinder???

Dori, is this a similar symptom to yours?

[Pebsi]

Just to finish this thread up from my end...

Changed out the fuel injectors for some refurb'd ones off ebay. Gave it a good blast to Notts and car now starts like a dream hot or cold.

FIXED!!!!