82 Corvette running problems
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Intermediate
Joined: Jul 2013
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When I checked the fuel pressure I checked it at the fuel filter. After I got the car running with the gauge hooked up the pressure is 35lbs at the fuel filter is that to high? Is there a better place to check it. Making progress will get back to it tomorrow.
Burning Brakes
Joined: Feb 2013
Posts: 1,062
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From: Burkburnett TX
You must have a good working fuel pressure regulator to hold back pressures that high. It is located in one of the throttle bodies, the drivers side I believe. You can rebuild the regulator with a kit pretty cheap. Also, the coolant temp sender has a very direct affect on the amount of fuel sent. Make absolutely sure its hooked up and working.
Le Mans Master
Joined: Jul 2000
Posts: 6,664
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From: columbia city in
You must have a good working fuel pressure regulator to hold back pressures that high. It is located in one of the throttle bodies, the drivers side I believe. You can rebuild the regulator with a kit pretty cheap. Also, the coolant temp sender has a very direct affect on the amount of fuel sent. Make absolutely sure its hooked up and working.
check the coolant sensor.the one in front .
Melting Slicks
Joined: Mar 2006
Posts: 2,248
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From: Warrington PA
Finalist 2020 C4 of the Year - Unmodified
the Fuel Pressure Regulator (spring) in the rear TBI (rear unit) is what controls the Fuel inlet pressure is calibrated @ 11 p.s.i.
also reading on how the IAC's really have a huge function in the idle control of fast & slow idle speeds. that being said, although its been probably mentioned a number of times in various threads, the Fuel Injector "O" rings should be checked for cuts, distorations, etc., as it could have an effect for those experiencing "Hard Starting" "Rough Idle" etc.
don't know what the proper reading at the fuel filter should be, but a number of owners have used the fuel line between the TBI's to obtain that reading. And there is a company that we know that sells a fuel line with a gauge installed for that location to always monitor the Fuel
Pressure.
also remember that the engine should be operated (driven) at road speeds for a number of miles, to reset the IAC's and adjust the idle at at a more accepable level.
Thread Starter
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The TB both were rebuilt. And the regulator. I would like more information on the fuel gauge made for the inline connection. I was told this car only had 59,000 original miles. I have no prof of that other than what the owner I bought it from told me. It did have AC belts and hoses on it. The carpet inside not worn like it has a lot of miles other than rotted from the sun. This car has been setting since 1995 in Palm Springs. I was thinking of replacing the oil and coolant sending unit any?
Melting Slicks
Joined: Mar 2006
Posts: 2,248
Likes: 67
From: Warrington PA
Finalist 2020 C4 of the Year - Unmodified
The TB both were rebuilt. And the regulator. I would like more information on the fuel gauge made for the inline connection. I was told this car only had 59,000 original miles. I have no prof of that other than what the owner I bought it from told me. It did have AC belts and hoses on it. The carpet inside not worn like it has a lot of miles other than rotted from the sun. This car has been setting since 1995 in Palm Springs. I was thinking of replacing the oil and coolant sending unit any?
second product down, which is currently out of stock.....
If its been sitting since 95, I would replace the fluids, hoses, thermostat, etc., just because of age and be done with it. Replacing the coolant temperature sensor (CTS) is also not a bad idea.
Remember you still need to get the car on the road so the IAC's will reset, before you can make any adjustments on your idle, if needed at all. Just trying to get it to idle correctly without resetting the IAC's is wasting your time. There I go again, sounding like a broken record.
On a side note, did some ignition upgrades on the 82 today that you may be interested in doing. So far test ride is very positive. Have to go out for the day, but will start a thread on it tonight. Stay tuned.
Taking the Vette, so I'll have a full product review tonight....
Thread Starter
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Yes I do plan on changing all the fluids etc. I was trying to get it to run good enough so I could get it smog ed you l now that California rule. I haven't driven it on the road because it's not licensed for the road yet. Would the IAC reset if running on jacks with tires off the ground? OK I did drive it to the station around the corner to fill it up with fuel.
Advanced
Joined: Apr 2013
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From: newtown ct
running on jack stands
it will work but be careful as I found out you must keep the rear arms at the same angle as if they were weighted on ground for u joint sake i had severe vibration and binding doing this and found out the hard way withe a tossed half shaft.way better to give it a midnite cruise if possible . good luck
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Thread Starter
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Well I gave the car a break today but just had to go start it up. It idled but rough I moved the distributor just to change the timing to see what happened. The car smoothed out an idled a lot better still running real rich but did idle. I will check the timing with a light to set it right. Just wanted to update making progress.
Melting Slicks
Joined: Jun 2011
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Well I gave the car a break today but just had to go start it up. It idled but rough I moved the distributor just to change the timing to see what happened. The car smoothed out an idled a lot better still running real rich but did idle. I will check the timing with a light to set it right. Just wanted to update making progress.
Safety Car
Joined: Mar 2007
Posts: 3,652
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From: Bridgewater nj
OK update. After suggesting changing plugs and remembering I had this happen before I went down and got a new set of plugs and changed them out. What do you know it now started. Still don't idle but runs at 2000 RPM or higher nice and smooth. Does seem to run rich,real rich. I unplugged the EGR and ran it straight to the TB seemed to be better but still running rich. Where the EGR plugs in on vacuum I noticed it was broke where it plugged in, that's why I went to the TB to see what happened. I can hold the throttle to where it is almost idling but went I let off it will die. so still got more work.
If the engine starts running good. Run it for a few days everyday with fresh gas. The ECU will learn and set the idle automatically but it does take a few good running cycles. Over an hour each. Until then idle may be high. Over a 1000 RPM. Idle on a CFI is about 650
If it doesn't smooth out and idle is ruff. The plenum base must be check for leaks and the EGR valve must be checked.
I high lighted the EGR comment. This possisbly could be your headache. Sometime they get stuck open and it lets exhaust gasses enter the intake. Stuck open and its nothing but a giant vacuum leak pumping in crap from the exhaust.
With your fingers, reach under the EGR and push on the diaphragm through the holes in the back. The car should stumble and die. If you car barely changes, chances are the EGR is stuck. Your fuel pressure is in a safe range.
Last edited by hugie82; Aug 4, 2013 at 09:43 PM.
Thread Starter
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Thanks for all your guys help. I was thinking of pulling the EGR valve off to check it out see if it was stuck, dirty etc. ESC thanks for reminding me of that, had read it in the book. It's getting closer. Made a lot of progress this weekend. I tried to put picture on here of the car. I got a message that I could only do that when I first signed up is that true?
Melting Slicks
Joined: Mar 2006
Posts: 2,248
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From: Warrington PA
Finalist 2020 C4 of the Year - Unmodified
Yes I do plan on changing all the fluids etc. I was trying to get it to run good enough so I could get it smog ed you l now that California rule. I haven't driven it on the road because it's not licensed for the road yet. Would the IAC reset if running on jacks with tires off the ground? OK I did drive it to the station around the corner to fill it up with fuel.
Now if you were on a dyno and strapped down properly, then that is a different situation. Better to be safe than sorry as they say...
You can post pics here, if you use photobucket it's real simple. There is a thread on how to do this, if you need help, let us know...
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Ok, I pulled the EGR valve off and it is stuck open. Froze could not move the diaphragm at all. So I think my troubles are about to be solved when I replace it. Will update this weekend when I replace it.
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Update: I sprayed wd-40 on the EGR valve and diaphragm is working fine . I reinstalled it Runs good at higher RPM still don't idle. I can hold the throttle at 1000 down to 500 RPM it will run and idle then. When I let off the gas it will go to about 300 RPM then die. Will a drive correct this I'm looking at going ahead and pulling the intake to make sure that it is sealed good. I don't think that is the problem. Also I need a new EGR solenoid relay where can I find one is there another year that will work?
Safety Car
Joined: Mar 2007
Posts: 3,652
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From: Bridgewater nj
Real rich is a vacuum leak or O2 sensor. The 02 sensor would through a check engine light so think vacuum leak. Did you check the plenum? Also it really is a must on CFI to pull the plenum, clean and install the Felpro gasket. Its not much and its not hard if you take your time.
You said you checked the EGR valve with wD40??? The diafram is not what you need to check. Its the plunger under the EGR that lets exhaust into the intake. If its stuck open your car will never idle. But you said, manually you can hold the car at 5-700 rpm a bad EGR would make it run very rough at that rpm and so would a plenum leak.
Also the IAS motor should be kicking in on cold starts. Your idle should shoot up to 1700rpm when cold. If its not, that motor in the TB is not working and needs to be cleaned or replaced.
You said you checked the EGR valve with wD40??? The diafram is not what you need to check. Its the plunger under the EGR that lets exhaust into the intake. If its stuck open your car will never idle. But you said, manually you can hold the car at 5-700 rpm a bad EGR would make it run very rough at that rpm and so would a plenum leak.
Also the IAS motor should be kicking in on cold starts. Your idle should shoot up to 1700rpm when cold. If its not, that motor in the TB is not working and needs to be cleaned or replaced.
Last edited by hugie82; Aug 11, 2013 at 01:43 PM.