occasional no start

[BoostedAWD91]

recently i have starting having a no start issue every so often. 2 days ago it started when i was leaving my house. the car died and then wouldnt start again so i thought it was my cop setup so i put my plug wires and coil pack back on and it fired right up. worked fine for 2 days and now today i went out and it started right up and ran it for awhile and shut it off. then tried to restart and it would putter alittle and then stall. tried again and then it just cranked and wouldnt even attempt to start for a few minutes. after waiting a minute i tried again and finially got it started but had to crank with the throttle fully opened. i am getting spark and have fuel pressure, the only thing i can think is the vpc unit is dying. any ideas?

 

[1990ggsxnj]

Could be a bunch of things. Fuel Solenoid (use jumper in engine bay to check), Filter Preventing correct pressure (what's your gauge reading), Pump preventing correct pressure (again, gauge reading but may be intermittant), CAS crapping out on you (Is oil leaking from there? What happens when you swap a good working one in there?). I've no experience with a VPC but can you remove it from the mix temporarily to see if it helps? I'm assuming you've checked your ECU already. There are more but these are off the top of my head.

 

[BoostedAWD91]

fuel pressure is around 40psi, cas is almost brand new. the vpc has been giving me problems and car hasnt been running the greatest so the only thing i can guess is it time to switch to dsmap

 

If your getting spark its not the CAS. Did you pull the plugs and verify that you were actually getting fuel in the cylinders? Pressure at rail doesn't mean its making it in the engine. Haven't screwed with VPC, but what are you seeing at the ECU (getting any crazy pressure, airflow, or TPS signals)? Have you thrown a logger on it?

 

[BoostedAWD91]

yes there is fuel getting in the cylinders and i looked through the logger and nothing seemed abnormal. all the readings are normal and no codes.
i have spark,fuel,compression so all their is left is its not reading the air sometimes.

when i played with it today, after sitting all night it fired right up and ran fine for 5-10 mins. i shut it off to get the tools away from the car and then got back in to pull the car into the garage and it wouldnt start.
i waited a few minutes and then it started again fine so /ubbthreads/images/graemlins/confused.gif

 

[Adorsey]

Are the connections to the battery and alternator tight?
If the wire on the alt. that is bolted in, is loose or moving around, it can make the car run just off the battery. That can make the car stall out while driving.
When she was running how were the dash lights?

This happened to me not to long ago

 

[MitchooO]

not exactly wat i have but mine would shut off and then i could start it in a few minutes... and i got it home and it sat for a few weeks... finally went to start it with a good batter and it would sputter just a little, and finally i got pissed and cranked it for like 5 minutes strait and it started to sputter more... i found the the wires on the thermostat housing must have been somehow grounding out or touching from being so brittle and thats why it owuldnt start, as soon as i put a new temp sensor in and rewired everything on the tstat housing it would start everything... easily at that... just my pennies... sryy if thats not it? /ubbthreads/images/graemlins/dunno.gif

 

[BoostedAWD91]

no the battery is fine, it cranks. if the connections were bad, i wouldnt have any power and be able to crank it.

 

[BoostedAWD91]

any other ideas

 

[1990ggsxnj]

Quoting MitchooO:
not exactly wat i have but mine would shut off and then i could start it in a few minutes... and i got it home and it sat for a few weeks... finally went to start it with a good batter and it would sputter just a little, and finally i got pissed and cranked it for like 5 minutes strait and it started to sputter more... i found the the wires on the thermostat housing must have been somehow grounding out or touching from being so brittle and thats why it owuldnt start, as soon as i put a new temp sensor in and rewired everything on the tstat housing it would start everything... easily at that... just my pennies... sryy if thats not it? /ubbthreads/images/graemlins/dunno.gif



Did you check your t-stat. My DSM had this problem and it's an easy fix. Especially when you use an angled connector on the end so the wire doesn't bend anymore.

 

[BoostedAWD91]

yeah the sensor harness is fine. The sensor and harness both have been replaced recently due to having that problem a few months back. I know that that isnt what is wrong this time as when the sensor fails, the ECU will read that the temp is -59 degree(not sure on exact reading) which causes alot more fuel to be added and therefore flooding the engine with fuel causing the no start. My logger is still reading normal temps so that isn't the issue. It seems to be more of a problem when the car is at operating temp. When its cold it fires right up but after running awhile and i shut it off and try to restart right away is usually when it wont start /ubbthreads/images/graemlins/dunno.gif

 

[steve]

The FPR solenoid is supposed to combat that. Is yours still hooked up? Most people remove it and never have an issue, but...

 

[sleepyvr4]

Idea -

is your fuel pump new? I know you said bfp is fine (is that while the car is running?)

at startup the fuel pump may not be building pressure. I'm dealing with that on 2 non dsm's right now...

???

 

[BoostedAWD91]

I have pressure instantly,the pump is? Years old as it was installed when I bought the car 2.5 years ago
. I have a aeromotive for so I don't have the solenoid anymore