Injector soak?
Thread Starter
Instructor
Joined: Jul 2009
Posts: 242
Likes: 7
From: Bowling Green KY
Injector soak?
I changed my injectors a while back on my 94 coupe, and put on a set of MSD wires with E3 plugs. The car runs great. Love it. The miss is gone, and has lots of power. BUT, since changing all that stuff, it doesn't start with the first try anymore unless it is warmed up. Sometimes it takes three or four attempts now. Also the other day after it started, it started backfiring and acting goofy, lurching and stuff before it smoothed out and was fine again. I pulled two plugs, wondering if one of my injectors wasn't leaking, but didn't smell or see gas. Before I pull the other plugs, do any of you have an idea what could cause this?
Thread Starter
Instructor
Joined: Jul 2009
Posts: 242
Likes: 7
From: Bowling Green KY
It just seems terribly coincidental to me that the problem would happen right after the injector change. I'm wondering if one of them is leaking fuel into the cylinder, causing a little flood condition that needs to get cleared.
Safety Car
Joined: Jun 2006
Posts: 3,629
Likes: 28
From: FL
I had a similar problem after installing Bosch II's, Jon exchanged them for a set of III's calibrated specifically for 93 cars, they cured my long crank time.
Give him a call after doing the above test to see if he has a suggestion.
Thread Starter
Instructor
Joined: Jul 2009
Posts: 242
Likes: 7
From: Bowling Green KY
Hi Toptechx6, I was hoping that you'd chime in. I've never done the fuel pressure guage thing, so I'll look around for a thread that explains it. Your advice is always good. When you come to the next Forum, I'll owe you a steak dinner.
Speaking of steaks, yesterday was the worst ever. I took my son out to lunch and when I got back in the car to leave it took awhile to start. When it did finally get going it ran very rough, and stalled a number of times as I sat there in the parking spot. I kept at it and eventually it smoothed out and ran like normal. I put it in gear, took off and it accellerated great, idled great and gave me no problems. I'm just picturing a cylinder filling up with gas while it is parked...
Thanks again for your help.
B2
Speaking of steaks, yesterday was the worst ever. I took my son out to lunch and when I got back in the car to leave it took awhile to start. When it did finally get going it ran very rough, and stalled a number of times as I sat there in the parking spot. I kept at it and eventually it smoothed out and ran like normal. I put it in gear, took off and it accellerated great, idled great and gave me no problems. I'm just picturing a cylinder filling up with gas while it is parked...
Thanks again for your help.
B2
Pro
Joined: Dec 2009
Posts: 502
Likes: 0
Vary easy to do, on the pass. side fuel rail, you will see a shrader valve pointing down, take off the 2 vacuum lines and unscrew the cap on the valve, then put your fuel pressure guage on and turn the ignition ON.
You need to pinch off the return valve by the gas cap. It is the hose on the bottom and comes in from the right. Use vise grips to pinch off(be vary careful not to pinch to hard and break the hose).
You need to pinch off the return valve by the gas cap. It is the hose on the bottom and comes in from the right. Use vise grips to pinch off(be vary careful not to pinch to hard and break the hose).
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Safety Car
Joined: Jun 2006
Posts: 3,629
Likes: 28
From: FL
Hi Toptechx6, I was hoping that you'd chime in. I've never done the fuel pressure guage thing, so I'll look around for a thread that explains it. Your advice is always good. When you come to the next Forum, I'll owe you a steak dinner.
Speaking of steaks, yesterday was the worst ever. I took my son out to lunch and when I got back in the car to leave it took awhile to start. When it did finally get going it ran very rough, and stalled a number of times as I sat there in the parking spot. I kept at it and eventually it smoothed out and ran like normal. I put it in gear, took off and it accellerated great, idled great and gave me no problems. I'm just picturing a cylinder filling up with gas while it is parked...
Thanks again for your help.
B2
Speaking of steaks, yesterday was the worst ever. I took my son out to lunch and when I got back in the car to leave it took awhile to start. When it did finally get going it ran very rough, and stalled a number of times as I sat there in the parking spot. I kept at it and eventually it smoothed out and ran like normal. I put it in gear, took off and it accellerated great, idled great and gave me no problems. I'm just picturing a cylinder filling up with gas while it is parked...
Thanks again for your help.
B2
One test you can do without a pressure gauge would be to remove the dipstick and smell the oil, if you do have a leaking injector the oil may be contaminated by the excess fuel that gets by the rings. Not very scientific of course but if it does smell like gas you are probably on the right track.
As good as Jons product and service I'm sure he would admit that an occasional bad injector gets through, again I will suggest calling him to consult, he may have some suggestions, good luck.
Last edited by toptechx6; Jul 27, 2010 at 07:29 AM. Reason: error
Melting Slicks
Joined: Jan 2009
Posts: 3,482
Likes: 196
From: folsom california
a leaking fuel injector can do more than fill a cylinder; in my own experience, over the course of letting the car sit for one week, the pan and crankcase were filled COMPLETELY with gasoline; all this from one injector that went drip, drip, drip.
Supporting Vendor
Joined: Mar 2008
Posts: 1,762
Likes: 14
From: Cumming Ga
Your imagination may not be that far off the mark. A word of caution; a leaking injector can indeed fill the cylinder with fuel and if that happens it is possible to damage the engine when restarting due to hydro-lock.
One test you can do without a pressure gauge would be to remove the dipstick and smell the oil, if you do have a leaking injector the fuel may be contaminated by the excess fuel that gets by the rings. Not very scientific of course but if it does smell like gas you are probably on the right track.
As good as Jons product and service I'm sure he would admit that an occasional bad injector gets through, again I will suggest calling him to consult, he may have some suggestions, good luck.
One test you can do without a pressure gauge would be to remove the dipstick and smell the oil, if you do have a leaking injector the fuel may be contaminated by the excess fuel that gets by the rings. Not very scientific of course but if it does smell like gas you are probably on the right track.
As good as Jons product and service I'm sure he would admit that an occasional bad injector gets through, again I will suggest calling him to consult, he may have some suggestions, good luck.
Jon
Team Owner
Joined: Mar 2001
Posts: 54,124
Likes: 30
From: Cincinnati, Oh USA
Black exhaust when it starts and runs rough, is a sign of too rich fuel caused by leaky injector/s. Fuel pressure should be 35-42 psi and hold up for at least 30 minutes with the ign off.
