QuestionHope all is well.
We exchanged e-mails two weeks ago.
Recall that I have a 1990 Plymouth Grand Voyager that has exhibited an issue in very hot conditions - the car will quit and the only remedy is to let it cool down - sometimes I need to wait as much as three hours before it will start. I beleive it is not getting fuel almost like a vapor lock.
You turned me on to the Coolant Temp Sensor (CTS) as a possible culprit. As an aside, I pursued some on-line research and came up with typical CTS failure causing cold performance problems - not my situation. Agree, however, that since I previously had retrieved a code 17 it was a worthwhile pursuit.
Before starting, I checked the codes and this time found only a code 22 -also related to the CTS.
I decided to replace the sensor.
The replacement sensor tested cold at 14,400 Ohms. Hot it tested at 740 Ohms.
I tested the old sensor too. Its reistance charateristics were very similar.
After replacing the sensor, I still had a code 22 but later it cleared so I am wondering if you must go through a few start run cycles before the old code is cleared??
You also mentioned in your e-mails last weekend that you actually thought it was possible for a multi-port EFI engine to vapor lock - suggesting cooling the lines might be a fix. Was wondering if you had a suggestion for how to do that.
Temps here in Colorado in late May early June are still cool so have not yet experienced the how weather flameout.
Also wanted to ask if you thought pursuing a fuel pressure "line of inquiry" might be worthwhile. Have a friend here in Colorado who had a similar problem with a Caravan and the dealer, in the end, replaced a defective fuel pressure regulator after he burned out a couple of fuel pumps. He claimed that the fuel pressure regulator caused the "flameout" condition.
One other line of inquiry I wonder about is the Auto Shutdown Relay (ASD) which controls the fuel pump. Do you know if there is any history of temperauture related issues with the ASD relay causing the fuel pump to either run intermittently or to completely shutdown?
Thanks
Randy
AnswerHi Randy,
Thanks for the kind remarks/evaluation.
Have you check the continuity of the coolant temp sensor wires from the plug to the pcm? The tan/ black goes to the pin 2 and the black/light blue to pin 4. Also look over the wires for a possible melt-through and gently flex the wiring while checking for continuity to see if it might be a weak connection. I don't have any suggestions on vapor lock except to check for any too close positioning of the fuel lines to the exhaust system and perhaps putting some insulation wrap on the lines. The fuel system pressure can be checked and is supposed to be 48 psi. There is a port on the fuel rail. I haven't heard of any ASD problem but if it were there it would likely cause a code 42.
Roland
