Help for an 87 coupe
Thread Starter
Intermediate
Joined: May 2013
Posts: 25
Likes: 1
From: Vancouver Washington
Help for an 87 coupe
Greetings to all...
I have appreciated all of the info I have received so far...but now a new issue has come up that has me absolutely stumped.
I took the vette out yesterday and drove it around for about 2 hrs....city and highway...just to blow out the spiders. ran great and lovin life.
Got it home into the garage and when I shut it off heard kind of a buzzing/clicking coming from the passenger side of the car. Went to start it back up and it idled horribly and oil pressure was registering about 4-6 lbs. If I push on the accelerator it runs fine...good oil pressure...about 50 lbs. I researched many threads as well as perusing the manual and everything pointed to the fuel oil pressure switch.
Long thread short, I have replaced both MAF relays, cleaned the MAF sensor, replaced the oil pressure sending unit, PVC valve, fuel pump and internal filter, fuel filter, and fuel pump relay. I have checked the FP fuse as well
Doing the exact same thing, but I did find a lot of little things to be corrected.
The car is throwing no codes ...except 12...and I have no idea what to look at now...
Any ideas?????
I have appreciated all of the info I have received so far...but now a new issue has come up that has me absolutely stumped.
I took the vette out yesterday and drove it around for about 2 hrs....city and highway...just to blow out the spiders. ran great and lovin life.
Got it home into the garage and when I shut it off heard kind of a buzzing/clicking coming from the passenger side of the car. Went to start it back up and it idled horribly and oil pressure was registering about 4-6 lbs. If I push on the accelerator it runs fine...good oil pressure...about 50 lbs. I researched many threads as well as perusing the manual and everything pointed to the fuel oil pressure switch.
Long thread short, I have replaced both MAF relays, cleaned the MAF sensor, replaced the oil pressure sending unit, PVC valve, fuel pump and internal filter, fuel filter, and fuel pump relay. I have checked the FP fuse as well
Doing the exact same thing, but I did find a lot of little things to be corrected.
The car is throwing no codes ...except 12...and I have no idea what to look at now...
Any ideas?????
Thread Starter
Intermediate
Joined: May 2013
Posts: 25
Likes: 1
From: Vancouver Washington
I forgot to mention that every time I did a cold start the motor would blow smoke like crazy.
Bad fuel or still think it's an injector?
Would I be looking at a whole bank or just one?
What is the best method for treating injectors?
By the way...thanks for the reply....
Bad fuel or still think it's an injector?
Would I be looking at a whole bank or just one?
What is the best method for treating injectors?
By the way...thanks for the reply....
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
The diaphragm in the fuel pressure regulator might have a hole in it. To check for that, remove the vacuum line from the fuel pressure regulator and look for fuel in the line.
You might have worn valve stem seals.
There might be a problem with the cold start injector. Try unplugging it and see how that affects things. Cranking time might be longer before the engine starts.
The ECM coolant temperature sensor on the front of the intake manifold might have a problem or there might be a bad connection. If the ECM sees an open in this circuit it will think the coolant temperature is -40° and will drastically enrichen the fuel mixture.
Thread Starter
Intermediate
Joined: May 2013
Posts: 25
Likes: 1
From: Vancouver Washington
Black smoke...
The fuel is about 2,5 yrs. old and it has stabil and sea foam in it...about 1/2 tank....I was trying to just burn the fuel up then fill it with good stuff...until this problem arose. I thought maybe it was just the sea foam burning through the system.
The fuel is about 2,5 yrs. old and it has stabil and sea foam in it...about 1/2 tank....I was trying to just burn the fuel up then fill it with good stuff...until this problem arose. I thought maybe it was just the sea foam burning through the system.
Melting Slicks
Joined: Jan 2008
Posts: 2,054
Likes: 120
From: AZ
Adding to the above, use your FP tester (have one?) to ensure it's proper, with pump running before start. during engine run, and if it holds when shutdown. Lots of threads on that, plus the FSM. Some of us tape it to the windshield for viewing ease.
Smell the dipstick for gasoline odor.
Don't allow this to go on too long as all that richness can ruin your CAT, or worse if the oil is diluting.
Smell the dipstick for gasoline odor.
Don't allow this to go on too long as all that richness can ruin your CAT, or worse if the oil is diluting.
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Team Owner
Joined: Sep 2003
Posts: 20,179
Likes: 673
From: Freedom is never more than one generation away from extinction.
St. Jude '03 thru '24
A bad injector can be dumping fuel full time when running and when the engine is off, dumps residual pressure/fuel into the manifold or if that valve is open, into the cylinder. Pull the plugs after she is cooled off and check for a wet or very oily plug/s. You gotta a lot of work to do.
Mind you this work isn't all that intensive but will use up a Saturday learning all the hoops and tricks to get the job done. Good news is you'll be and expert when all is finished.
Melting Slicks
Joined: Apr 2011
Posts: 3,496
Likes: 475
From: New Jersey
Take a block of wood and a hammer and tap each injector several times firmly but carefully. This may free it up and saves a lot of time. It works sometimes, trust me. If it does get some Techron and use it.
Thread Starter
Intermediate
Joined: May 2013
Posts: 25
Likes: 1
From: Vancouver Washington
I put a pressure gauge on the shrader valve and got the following readings:
Key on- 45# for 2 seconds
After 2 seconds-drops to 41 #
Let sit for 68 minutes- drop to 25#
Started engine and took to 1200rpm- bounces between 46 and 48#
Took foot off of throttle...instantly dies
When I started it oil pressure was about 78 lbs.
What the heck am I missing?
Thread Starter
Intermediate
Joined: May 2013
Posts: 25
Likes: 1
From: Vancouver Washington
Ok...pulled The plugs..all looked fine,checked the new fuel pump...comes on for 2 seconds then shuts off as it should,pulled the vacuum line from the fuel pressure regulator...no gas smell or fuel spill,tapped on the injectors.
I put a pressure gauge on the shrader valve and got the following readings:
Key on- 45# for 2 seconds
After 2 seconds-drops to 41 #
Let sit for 68 minutes- drop to 25#
Started engine and took to 1200rpm- bounces between 46 and 48#
Took foot off of throttle...instantly dies
When I started it oil pressure was about 78 lbs.
What the heck am I missing?
I put a pressure gauge on the shrader valve and got the following readings:
Key on- 45# for 2 seconds
After 2 seconds-drops to 41 #
Let sit for 68 minutes- drop to 25#
Started engine and took to 1200rpm- bounces between 46 and 48#
Took foot off of throttle...instantly dies
When I started it oil pressure was about 78 lbs.
What the heck am I missing?
Thread Starter
Intermediate
Joined: May 2013
Posts: 25
Likes: 1
From: Vancouver Washington
Thread Starter
Intermediate
Joined: May 2013
Posts: 25
Likes: 1
From: Vancouver Washington
Cylinder#:
1-16.2 ohms...2.3 at the connector
3 -16.1 ohms...2.3 at connector
5 - 16.2 ohms...2.8 at connector
7 - 16.2 ohms...2.8 at connector
Cold start - 3.7 ohms...0.4 at connector
2 - 16.1 ohms...4.4 ohms at connector
4- 16.1 ohms...4.4 at connector
6 - 16.1 ohms... 4.3 ohms at connector
8- 16.2 ohms...4.3 ohms at connector
Car reeks of fuel at the exhaust when running..
Still pointing to the FPR?
All help is greatly appreciated
Melting Slicks
Joined: Jan 2008
Posts: 2,054
Likes: 120
From: AZ
Not having a cold start injector car, I suspect that one is identical to the others and should test the same. An easy, cheap test is to unplug it and observe how it runs, especially when warmed up and the CS should be out of the ECM's picture, so to speak.
Team Owner
Joined: Sep 2003
Posts: 20,179
Likes: 673
From: Freedom is never more than one generation away from extinction.
St. Jude '03 thru '24
Based on your exam, all the fuel system components are functioning normally.
9th injector may be the problem, only one way to find out.
Pull the plug OR pull the injector and block off the hole
Team Owner
Joined: Sep 2003
Posts: 20,179
Likes: 673
From: Freedom is never more than one generation away from extinction.
St. Jude '03 thru '24
However IF this injector remains open, it will continue to dump fuel after the start sequence.
Of course pulling the plug should have nothing to do with the problem....