'92 will only start and idle after a rain
Thread Starter
Instructor
Joined: Apr 2007
Posts: 134
Likes: 0
From: new albany mississippi
'92 will only start and idle after a rain
1992, automatic, base model, 65,000 miles, has become impossible to start without stepping on the gas pedal while cranking, then will BARELY idle (if it does) when you take your foot off the gas pedal. Idles under 500rpm on the dash tachometer. Once the car has warmed up it gets better, And will fire immediately without touching the pedal. Only code stored is 43.
But here's the kicker: if it has rained, It fires up like a champ from a cold start, no pedal help, idles/runs fine.
No garage. Driveway car. Haven't had the cover on it since all this started, as it WAS my daily driver.
Free beer for the winner! Thanks, Eric
But here's the kicker: if it has rained, It fires up like a champ from a cold start, no pedal help, idles/runs fine.
No garage. Driveway car. Haven't had the cover on it since all this started, as it WAS my daily driver.
Free beer for the winner! Thanks, Eric
Drifting
Joined: Dec 2007
Posts: 1,647
Likes: 4
From: Argillite KY
I may be off base here but if you have an open knock sensor a code 43 will be set. As a by-product of the open KS the PCM/ECM will retard the timing to a preset amount. Retarded timing, if far enough, will make it hard to start. The rain thing throws me so just disregard it.
I believe the Knock sensor "talks" to the Electronic spark control module to make this happen. If the ESC doesn't talk to the ECM the max retard will occur. Usually about 20 degrees.
1) Open or shorted knock sensor
2) Loose knock sensor
3) Excessive mechanical noise within engine
4) Improper or incorrectly installed PROM or CALPACK in the ECM or defective ECM
5) Intermittent open in the EST line to the ignition module
I believe the Knock sensor "talks" to the Electronic spark control module to make this happen. If the ESC doesn't talk to the ECM the max retard will occur. Usually about 20 degrees.1) Open or shorted knock sensor
2) Loose knock sensor
3) Excessive mechanical noise within engine
4) Improper or incorrectly installed PROM or CALPACK in the ECM or defective ECM
5) Intermittent open in the EST line to the ignition module
Last edited by 1963SS; Oct 25, 2011 at 10:31 AM.
Drifting
Joined: Aug 2010
Posts: 1,704
Likes: 8
[QUOTE
1) Open or shorted knock sensor
2) Loose knock sensor
3) Excessive mechanical noise within engine
4) Improper or incorrectly installed PROM or CALPACK in the ECM or defective ECM
5) Intermittent open in the EST line to the ignition module[/QUOTE]
According to the shop manual, code 43, trouble chart- all these condition are related to a bad idling or stall or hard start up.
If a noisy engine produces excessive noise during crancking, knock sensor,as a detonation event,send to EST a signal,EST drops voltage to ECM terminal B7 under 6 v.,istantly ECM retard timing and you have an hard start up
1) Open or shorted knock sensor
2) Loose knock sensor
3) Excessive mechanical noise within engine
4) Improper or incorrectly installed PROM or CALPACK in the ECM or defective ECM
5) Intermittent open in the EST line to the ignition module[/QUOTE]
According to the shop manual, code 43, trouble chart- all these condition are related to a bad idling or stall or hard start up.
If a noisy engine produces excessive noise during crancking, knock sensor,as a detonation event,send to EST a signal,EST drops voltage to ECM terminal B7 under 6 v.,istantly ECM retard timing and you have an hard start up
Racer
Joined: Aug 2011
Posts: 494
Likes: 138
From: Chesapeake, VA
Can't ignore the rain factor.....the air becomes a bit denser/cooler during rain. I almost think it's running rich and the denser air helps. Possibilities include, FPR, MAP sensor, vacum leak.
....or maybe the denser air allows for more fuel which helps with the very retarded timing.
....or maybe the denser air allows for more fuel which helps with the very retarded timing.
Melting Slicks
Joined: Dec 2008
Posts: 2,772
Likes: 64
From: Mystic CT
Why not clear the code and see if it comes back... History is just that and you have no idea of when it was set if you have not checked in a while such as before the problem and they were clear then. It would have been real handy if GM included a counter that kept track of how many times a code was set only one byte of info for up to 256 times..
Last edited by ddahlgren; Oct 25, 2011 at 12:56 PM.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
5 Best & 5 Worst Corvette Daily Drivers
Joe Kucinski
The Headlights of Every Corvette Generation Explained
Joe Kucinski
5 Best & 5 Most Overrated Corvette Track Packages of All Time!
Joe Kucinski
Every 2027 Corvette Engine Explained
Joe Kucinski
Designer Imagines A Corvette That Looks More Like a Corvette Than the Corvette
Verdad Gallardo
10 Ugly Corvettes That We Still Kinda Love
Joe Kucinski
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
Drifting
Joined: Dec 2007
Posts: 1,647
Likes: 4
From: Argillite KY
Can't ignore the rain factor.
The biggest clue would be the code 43. That can easily be the cause of his symptoms.
You have a very rare C4 one that likes rain and cold..LOL
Don't really try this. I would hope you know better but there have been some very.......uh............. unformed folks on the forums.
Last edited by 1963SS; Oct 25, 2011 at 01:27 PM.
Le Mans Master
Joined: Aug 2010
Posts: 9,272
Likes: 17
Sure you can.......watch this..................................Ig nored. All Done!!
The biggest clue would be the code 43. That can easily be the cause of his symptoms.
Maybe he could sprinkle some water on the Opti and make the hard starting go away. Add a "T" to the windshield washer line, run a separate hose to just below the water pump, tie it aff and just and clean the windows before starting. Don't really try this. I would hope you know better but there have been some very.......uh............. unformed folks on the forums.
The biggest clue would be the code 43. That can easily be the cause of his symptoms.
Maybe he could sprinkle some water on the Opti and make the hard starting go away. Add a "T" to the windshield washer line, run a separate hose to just below the water pump, tie it aff and just and clean the windows before starting.
Don't really try this. I would hope you know better but there have been some very.......uh............. unformed folks on the forums.so...first you're sprinkling prozac, then you're sprinkling water, this could end badly.