I'm screwed....
Team Owner
Joined: Aug 2000
Posts: 40,156
Likes: 45
From: San Pedro CA
remove the rail from the intake, and turn on the key... watch what flows out.
before you do start the car, be sure to squirt a little oil into each cylinder, and crank it without spark or plugs installed. This will allow for the excess fuel to blow out.
before you do start the car, be sure to squirt a little oil into each cylinder, and crank it without spark or plugs installed. This will allow for the excess fuel to blow out.
Team Owner
Joined: Aug 2000
Posts: 40,156
Likes: 45
From: San Pedro CA
Originally Posted by Corvette Kid
Yes and so that is how it maintains pressure. If it fails it will simply not allow this. I suppose perhaps it's possible, but I've never heard of or run across one failing and causing excessive pressure.
The pump can deliver about 100 PSI.
The FPR steps that down to 40 PSI.
What happens when the FPR can't contain the pressure any longer?
Burning Brakes
Joined: Apr 2005
Posts: 1,227
Likes: 0
From: Atlanta Ga
i had same thing happen to me other week. Come to find out, the injector harness was grounding out against the block (rubbed wire) and was holding injectors open. wiggle the injector harness and see if you get pressure, or with key on and engine off see if you can make the injectors click/fire
left me stranded couple times. My symptoms were exact as yours.
I also flooded my engine...no issue after getting oil changed
left me stranded couple times. My symptoms were exact as yours.
I also flooded my engine...no issue after getting oil changed
Last edited by JustForFun; Jul 22, 2006 at 11:14 PM.
Thread Starter
Drifting
Joined: Dec 2005
Posts: 1,309
Likes: 20
From: Woodstock Georgia
Originally Posted by JustForFun
i had same thing happen to me other week. Come to find out, the injector harness was grounding out against the block (rubbed wire) and was holding injectors open. wiggle the injector harness and see if you get pressure, or with key on and engine off see if you can make the injectors click/fire
left me stranded couple times. My symptoms were exact as yours.
I also flooded my engine...no issue after getting oil changed
left me stranded couple times. My symptoms were exact as yours.
I also flooded my engine...no issue after getting oil changed
Team Owner
Joined: Mar 2001
Posts: 54,124
Likes: 30
From: Cincinnati, Oh USA
You have one or more injectors held open either because a defective injector/s or a wire grounded or defective ECM injector driver holding the injector wire to ground. That is the only way to get gas into a cylinder, through an injector. All cylinders had gas because the 86 does batch fire with the injectors, not sequential fire.
Le Mans Master
Joined: Jan 2003
Posts: 5,858
Likes: 7
From: Santa Maria CA
Originally Posted by bogus
remove the rail from the intake, and turn on the key... watch what flows out.
before you do start the car, be sure to squirt a little oil into each cylinder, and crank it without spark or plugs installed. This will allow for the excess fuel to blow out.
before you do start the car, be sure to squirt a little oil into each cylinder, and crank it without spark or plugs installed. This will allow for the excess fuel to blow out.
And make sure that the main connector to the distributor is connected ( the multi terminal one at the base), or you will get no fuel spray from the injectors when you turn the key. The computer needs an RPM signal from the pick up coil in the distributor in order to allow this. This is for an L98.
Doing this test should tell you something. When you ohm test an injector, it only tells you part of the story. It won't tell you anything about leaks or bad spray patterns. A visual inspection of the injector nozzles under fuel spray is needed.
Last edited by 86PACER; Jul 23, 2006 at 06:52 AM.
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Thread Starter
Drifting
Joined: Dec 2005
Posts: 1,309
Likes: 20
From: Woodstock Georgia
A-ha! A clue! I went out this morning and pulled off all of the injector harnesses. Now I've got pressure at the rail. It's still falling. So, I pulled the plugs, rolled up some shop towels really tight, and stuck them into the plug holes. As the pressure drops, I'll check the towel to see which cylinder is still receiving fuel (since none should).
There is some great info here, thanks guys for all of the input. I will keep everyone posted.
For what it's worth, these are brand new FMS 42# injectors, with a brand new Walbro 225 lph fuel pump, sock and filter. I did use a used AFPR, so that may certainly be a weak point.
There is some great info here, thanks guys for all of the input. I will keep everyone posted.
For what it's worth, these are brand new FMS 42# injectors, with a brand new Walbro 225 lph fuel pump, sock and filter. I did use a used AFPR, so that may certainly be a weak point.
Thread Starter
Drifting
Joined: Dec 2005
Posts: 1,309
Likes: 20
From: Woodstock Georgia
Results: I built the pressure back into the rail to 30#. With the shop towels inserted in the plug holes, I waited for the pressure to drop significantly (I checked the towel at around 9#). Cylinders 4 and 5 were wet with fuel. Now a question: If the cold start injector was bad and leaking, would the fuel primarily flow to these cylinders as it dripped from the injector?
Le Mans Master
Joined: Oct 2003
Posts: 6,130
Likes: 2
From: seattle WA
I'd bet the farm it's not the cold start injector. What I'd suggest is Ohming the injectors. And it seems to me if the regulator were bad you would eventually lose all pressure...I'll stick with what I first said, bad injector(s) I think you have a few sticking open. If you read the section in your FSM about how a cold start injector works...you'd see why I bet against that.
Team Owner
Joined: Aug 2000
Posts: 40,156
Likes: 45
From: San Pedro CA
we don't know what intake valves are open right now.
The theory sorta stands up, but with valves in various degrees of open, it's not proving everything. Remove the rail and try this again.
The theory sorta stands up, but with valves in various degrees of open, it's not proving everything. Remove the rail and try this again.
Thread Starter
Drifting
Joined: Dec 2005
Posts: 1,309
Likes: 20
From: Woodstock Georgia
I ohm'd the injectors. If I did this right (and, hey, that's debatable: I used the resistance setting 2000 on my volmeter). All injectors are 16 except the start injector which is 5. If the wifey lets me, I'll pull the rail later today (I'm on that proverbial thin ice since I've been out there the better part of two weekends).
Le Mans Master
Joined: Oct 2003
Posts: 6,130
Likes: 2
From: seattle WA
Well, that proves the injector coils are fine...don't think that actually proves none are sticking open or leaking though.
HEY, I'm always on thin ice with the wifey..after 37 years think she'd get used to it.
HEY, I'm always on thin ice with the wifey..after 37 years think she'd get used to it.
Thread Starter
Drifting
Joined: Dec 2005
Posts: 1,309
Likes: 20
From: Woodstock Georgia
So 5 ohm resistance is ok for the start injector? I'm going to pull the rail here in a few minutes. I'm going to pressurize the rail, with the harnesses removed and look for leaks. After, I'll reattach the harnesses and pressurize the system to see if any are sticking open.
I'm resurfacing a set of ZR-1 rims at the same time. Too little time......
I'm resurfacing a set of ZR-1 rims at the same time. Too little time......