Need Help
Thread Starter
Pro
Joined: Oct 2007
Posts: 739
Likes: 52
From: Reno NV
Need Help
1994 Coupe 6 speed
Took my car to Sacramento yesterday. Soon as I got there my car acted weird for one second and check engine light came on. Car still drove fine until I stopped. Then the car would not start back up for 30 minutes. Then when it started I could hear this plastic clicking sound from engine. I hope its not opti cause I just replaced one
I drove down the street and the click went away. Got on the freeway and the car was at no loss of power. Drove all the way back to Reno no problems but check engine light is still on with no codes except c12. Now its hard to start sometimes.
Anything I should check out ? Any help would be appreciated.
Took my car to Sacramento yesterday. Soon as I got there my car acted weird for one second and check engine light came on. Car still drove fine until I stopped. Then the car would not start back up for 30 minutes. Then when it started I could hear this plastic clicking sound from engine. I hope its not opti cause I just replaced one
I drove down the street and the click went away. Got on the freeway and the car was at no loss of power. Drove all the way back to Reno no problems but check engine light is still on with no codes except c12. Now its hard to start sometimes.Anything I should check out ? Any help would be appreciated.
Le Mans Master
Joined: Jan 2006
Posts: 5,621
Likes: 206
From: Orlando FL
Could the clicking be an arcing or sparking. Inspect the engine running in a dark area. Look around all plug wires, coil and especially coil wire where it goes thru water pump. Make sure the wires are on all the way in.
Are you using the on board diagnostics to check the codes in all modules? Re check codes periodically.
Does not sound like an opti problem. But does sound like a possible ICM going bad. Substitution is best way to check it.
Hard to start.. How long does it take to start?
Are you using the on board diagnostics to check the codes in all modules? Re check codes periodically.
Does not sound like an opti problem. But does sound like a possible ICM going bad. Substitution is best way to check it.
Hard to start.. How long does it take to start?
Le Mans Master
Joined: Jan 2006
Posts: 5,621
Likes: 206
From: Orlando FL
Sounds like your on to something. The fuel pump should run for 2 seconds and pressurize the system when you turn the key to on and pressure should stay up.
When the oil pressure comes up (closes pressure switch) it keeps the fuel pump running. So when turning over the pump can come on late and crank a lot when there is no initial pressure. That is one possibility. Or the fuel pump can be just going bad and just doesn’t always run as the day it quit on you. I would check to see if it is getting voltage to it when key is turned on for starters.
When the oil pressure comes up (closes pressure switch) it keeps the fuel pump running. So when turning over the pump can come on late and crank a lot when there is no initial pressure. That is one possibility. Or the fuel pump can be just going bad and just doesn’t always run as the day it quit on you. I would check to see if it is getting voltage to it when key is turned on for starters.
Thread Starter
Pro
Joined: Oct 2007
Posts: 739
Likes: 52
From: Reno NV
Car is really hard to start with service engine light on. I replaced the fuel pump it did nothing. Also I noticed the fans come on all the time.
Last edited by RogerZ06; Nov 19, 2008 at 07:30 PM.
Racer
Joined: Apr 2005
Posts: 484
Likes: 5
From: Madison Wisconsin
You may want to check your ECM for the presence of any codes. I just checked my manual and one of the reasons the fans will come on is if any diagnostic code is set. According to my 1993 shop manual, the ECM will turn on the primary fan if any of the following are present:
Diagnostic code is set
ECT above 219 degrees F
Engine oil temp above 270 degrees F
A/C head pressure above 189 psi
The secondary fan is turned on if any of the following conditions are present:
Diagnostic code is set
ECT above 226 degrees F
Engine oil above 277 degrees F
A/C head pressure aboe 225 psi
Assuming none of the standard things (coolant / oil temps, A/C) are calling for the fans, its probably the ECM either registering a code, or starting to have some issues.
Good luck,
Jim
Diagnostic code is set
ECT above 219 degrees F
Engine oil temp above 270 degrees F
A/C head pressure above 189 psi
The secondary fan is turned on if any of the following conditions are present:
Diagnostic code is set
ECT above 226 degrees F
Engine oil above 277 degrees F
A/C head pressure aboe 225 psi
Assuming none of the standard things (coolant / oil temps, A/C) are calling for the fans, its probably the ECM either registering a code, or starting to have some issues.
Good luck,
Jim
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Melting Slicks
Joined: Feb 2008
Posts: 3,286
Likes: 6
From: Palm Beach
The pump is initially run as you stated. However, it is again commanded on by the ECM as soon as you crank the engine and ignition pulses are received. The oil pressure switch only comes into play if the fuel pump relay fails.
Thread Starter
Pro
Joined: Oct 2007
Posts: 739
Likes: 52
From: Reno NV
I also flushed the coolant when I put new optispark and water pump on. I ran straight water for few months in summer. I just replaced the coolant 2 - 3 weeks ago before this happened with 50/50.
Thread Starter
Pro
Joined: Oct 2007
Posts: 739
Likes: 52
From: Reno NV
When cold she starts but runs rough for 20 seconds, Then shes fine. Finally got some codes to pop up.
Looks like I might be installing new opti and ICM.
H36 Distributor Ignition System High Pulse.
H42 Ignition Control Circuit Shorted.
Now I know why fans kicking on.
H62 Engine Oil Temperature Sensor Circuit Voltage Low.
Oh yea forgot to mention that its msd opti with 5k miles on it
Looks like I might be installing new opti and ICM.
H36 Distributor Ignition System High Pulse.
H42 Ignition Control Circuit Shorted.
Now I know why fans kicking on.
H62 Engine Oil Temperature Sensor Circuit Voltage Low.
Oh yea forgot to mention that its msd opti with 5k miles on it
Last edited by RogerZ06; Nov 25, 2008 at 02:02 AM.