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I'll only drive 6 hours for a good cheesesteak and a beer. For 8 hours it better be a steak and scotch
I'm just a simple Hillbilly. Anyone can grill some cow meat but only Philly pholk (folk) can make a Philly cheesesteak. I do have three single malts in the liquor cabinet and some choice ribeyes in the fridge. The only blended Scotch I enjoy is Ambassador 25 but I can't afford to drink it.
 

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Discussion Starter #22
I replied to your PM and you have some things to try. If we get it fixed I'll drive 8 hours for a good cheesesteak and a beer. Are you buying?:laughing:
Heck, I'll even toss in a tour of Old Philadelphia. Or, we could just visit Chinatown for a Rub-N-Tug lol:thumbsup:
 

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Or, we could just visit Chinatown for a Rub-N-Tug lol
I don't know what that is. I know what it sounds like but am not sure. A massage parlor?? I went to one of those in Saigon a long time ago. The sign said, "Tammy's Massage Parlor. We specialize in stiff joints". They did and 300,000 USP units of penicillin twice a day for three days cured me.
 

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Discussion Starter #24 (Edited)
Well, it appears the MCS will CLICK when I run a HOT & GROUND wires to it. Also, it will CLICK when plugged in and I force GROUND the negative/grey wire.

So, that's suggests the MCS is at least functional.


Next test (not looking forward to it) is to locate those 2-MCS wires (look like pink & Tan) entering the ECM and test to see if I can force the MCS to click there. If it does, then I'm to assume the ECM is bad?


If, the ECM is bad...who sells the best re manufactured replacement with the best warranty?


*special thanks to 1963SS for walking me through the test procedures :thumbsup: (cause I suck at electrical issues)
 

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Well, it appears the MCS will CLICK when I run a HOT & GROUND wires to it. Also, it will CLICK when plugged in and I force GROUND the negative/grey wire.

So, that's suggests the MCS is at least functional.


Next test (not looking forward to it) is to locate those 2-MCS wires (look like pink & Tan) entering the ECM and test to see if I can force the MCS to click there. If it does, then I'm to assume the ECM is bad?


If, the ECM is bad...who sells the best re manufactured replacement with the best warranty?


*special thanks to 1963SS for walking me through the test procedures :thumbsup: (cause I suck at electrical issues)
CARDONE Is a pretty good aftermarket electronic automotive rebuild name to look for.
There should be a plug in E-prom chip you need to transfer to the replacement ECM.

Look at Napa.
O'Reilley Auto.
Advanced Auto.
Autozone.

Google the ECM Number off of yours.
Should be a White Tag on the ECM unless it fell off after 40 years.
 

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First the disclaimer. I’m 750 miles away from my extensive notes and service manual on the E4ME. You’ll have to trust to my memory and that ain’t good.

If it’s clicking, that means your solenoid is working. Very good start. Likely means your computer is still alive too. Is the check engine light on? Does it light up when you start?
 

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Discussion Starter #27
First the disclaimer. I’m 750 miles away from my extensive notes and service manual on the E4ME. You’ll have to trust to my memory and that ain’t good.

If it’s clicking, that means your solenoid is working. Very good start. Likely means your computer is still alive too. Is the check engine light on? Does it light up when you start?
MCS only 'clicks' if I force ground the 'ground wire' with key-on (I believe) it's Gray or Tan in color...difficult to tell.


When I turn-on the key CEL comes on then goes off when engine is running...HOWEVER...MCS is NOT clicking anymore.


When I disconnect the MCS Plug and apply a separate HOT and GROUND wire directly to the MCS it will click every time I insert/remove the temp Ground Wire.


*testing with a 12v Test-Light, MCS plugged in, key on and I stab each of the two wires from MCS Plug BOTH Pink and Gray light Test Light = both HOT.


*with MCS unplugged and I test both inner sockets on the Plug...the faded Pinkish wire lights Test-Light-HOT and the Tan/gray wire is dead-grounded.


*where I'm at now...I had the battery unhooked for a few days (father in nursing home) and I had hopes once I reconnected the Battery the MCS would start clicking again when key is on...NOPE!


*I started the engine and unplugged the MCS...the engine imeditaly idled better but the CEL came on. Plug the MCS back in, engine drops RPM and idles poorly but...CEL goes out.


*I checked for codes by jumping the two far left sockets in the plug under the Ashtray.
*turn key to 'on'...MCS starts clicking and CEL light flashes **-***, **-***, **-*** over and over for a dozen plus times, no other sequence of CEL light.


*I'm getting PISSED...I remove drivers seat, yank the battery, yank the Computer (nothing easy on these cars to work on)

*** my next thing is to somehow locate the two DISCOLORED wires at the MCS and find out where those same non-discolored wires enter the two large plugs that go into the computer, and check for continuity to make sure the run from MCS to ECM Plug is good...AND...if I get LUCKY enough to locate those two wires I'll attempt to run a 12v hot and GROUND to those wires to see if the MCS clicks. That test should prove the wires between the MCS to ECM are good and I would then assume the ECM is bad???


***maybe someone can confirm: are the two wires at the MCS Pink w/a black stripe (hot) and the other wire Gray w/a black stripe ground??? (I'm not 100% sure of the Gray ground wire)

The wires going into the ECM plugs have good color, the two going into one of the ECM Plugs are faded bad but one looks somewhat Pink and the other Tan/Gray.


*** so that's where I'm at...I don't have much more hair to pull out, and I suck at wires/electronic diagnosing. But I can do everything else!

I need this Car up and running because if my Diesel Truck craps the bed I have no way to get to my Fathers nursing Home and my daily visits are paramount, he's not well.
EDIT...I remember sometime in 1983 I took the car to my local Chevrolet dealer for an issue and the ECM had an extended 5-year warranty. Sure enough the ECM I just pulled out was a GM Remanufactured, I purchased the car new in 81.
 

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I don't know what that is. I know what it sounds like but am not sure. A massage parlor?? I went to one of those in Saigon a long time ago. The sign said, "Tammy's Massage Parlor. We specialize in stiff joints". They did and 300,000 USP units of penicillin twice a day for three days cured me.
Code 12 means No Problems all is OK.


Real simple primitive early Computer command control.
Likely written in ASC 2 I learned in college.
Intel 8085 microprocessor.
Lez was one of my Professors.
He claimed he invented it.
He was a US Navy man.


My other professor claimed he invented the 1st LCD screen.
Both were Nuts.


We used to tease Lez....Get bored writing in ASCII.
ASK LEZ....ARE YOU HIGH AGAIN TODAY LEZ ?
HE WOULD REPLY YES I AM GUYS.
NOW COME ON GUYS BE WITH NOW.
THIS IS REAL IMPORTANT.
YOU ALL MUST KNOW THIS.'
YOU ARE THE FUTURE LEADERS. :cheers:
 

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Discussion Starter #29
"Code 12 means No Problems all is OK."
So, **-*** repeated over and over means "no problems all is ok" then why is the MCS not functioning, clicking?
Could the problem still be within the Carburetor?
Maybe a bad Float, maybe a heavy Float, Mice living in the Carb or possible bad muffler bearings??? :bang:drink:
 

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"Code 12 means No Problems all is OK."
So, **-*** repeated over and over means "no problems all is ok" then why is the MCS not functioning, clicking?
Could the problem still be withing the Carburetor?
Maybe a bad Float, maybe a heavy Float, Mice living in the Carb or possible bad muffler bearings??? :bang:drink:
I am working on an old 1994 Chevy C1500 pickup at work.
4.3 Liter V6.
Towed in.
Truck sat for several years.
The other mechanics fiddled with.
Walked away.
I like working on older vehicles & know more about than they do.
To my surprise it was filled with 22 gallons of water in the gas tank.
I hot wired the electric fuel pump on with the fuel pump relay removed & a Jumper wire from terminals "A" & "E".


I was catching in 5 gallon cans.
Filed them up with water.
Crystal Clear Tap water. I don't think rain water.
The rest I just let run on the ground.


I put 5 gallons of fresh 87 octane gas in & it took off running.
All came over & asked WHAT DID YOU DO BRIAN ? ITS RUNNING AGAIN !


Something I never ever seen prior.


Anything is possible. :cheers:
 

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Believe it or not you're getting closer. When you did the CEL code you were getting a ** ***, ** ***. correct?
That indicates a code 23. Two flashes followed by three flashes. Code 23 is mixture control solenoid either open or grounded. We already knew that.

When you jumped the pins on the ALDL plug and the MCS started clicking, that alone tested the MCS circuit and it appears to be working normally. The ECM is doing it's job and forcing the "clicking". Thanks for the new information.

Here's a pic of the ECM wiring........don't be scared.:laughing:



Do you see wires #9 and #14. Use you multimeter to check the voltage on those two wires. If the O2 sensor is open it will be telling the ECM that it is very rich and it will ground the MCS to lean it out. If it keeps it grounded then it won't "click".

Start the car and let it warm up a while. Set your meter on the lowest voltage scale. You are looking for something between .2 volts and .9 volts. or 200 millivolts and 900 millivolts. This is an older and very rudimentary O2 sensor and I'm not sure if it would throw it's own code or not. if it's not running.

When you said that it ran better when you unplugged the MCS that's telling me that it was energized (wire #18 grounded by the ECM)and giving a full rich limp mode. That could be telling me that the O2 sensor isn't working. Sorry for the trouble but sometimes checking is all that we can do to find the problem.

Let the car warm up and see if it's giving any more codes other than #23. and check the millivolts on the O2 sensor wires #9 and #14. I think we're starting to get a leg up on this issue.
 

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I am going to let Gunny handle the Electronics end of your Corvette.

Something to check is the Fuel Filter.
Its located on the Q-jet inlet.
Need a 5/8" inch line wrench.
And a 7/8" or 1.00" open end wrench.
Remove the fuel filter.
Look for debris contamination.
Post a photo if you can.
 

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Discussion Starter #33
I am going to let Gunny handle the Electronics end of your Corvette.

Something to check is the Fuel Filter.
Its located on the Q-jet inlet.
Need a 5/8" inch line wrench.
And a 7/8" or 1.00" open end wrench.
Remove the fuel filter.
Look for debris contamination.
Post a photo if you can.
Yes Sir, I know where the Filter is but, if dirty that should effect off Idle Engine performance too...at least I would think. And again the MCS stopped clicking, actually I don't recall the last time it did...but the Engine ran good.
Again, it just seems to be coincidence this all came about not too long after I filled the tank with 16 gallons of fuel.
If it is 'bad gas' then it should also effect cruising speeds.
 

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Yes Sir, I know where the Filter is but, if dirty that should effect off Idle Engine performance too...at least I would think. And again the MCS stopped clicking, actually I don't recall the last time it did...but the Engine ran good.
Again, it just seems to be coincidence this all came about not too long after I filled the tank with 16 gallons of fuel.
If it is 'bad gas' then it should also effect cruising speeds.
Only takes a few minuted to check the fuel filter.
I never liked the E4MC Q-jet much myself.
Built for Emissions.

Stop gap before GM went to Electronic Fuel injection.
TBI & TPI.
 

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Discussion Starter #37
Cliff is Ok.
Has a website Forum just for Q-jets.
He works alot.

Pontiac Drag racer too on the street.

Be nice if you can ger that Q-jet working right.
This Car is wearing me down...not looking for a Pity Party or Sympathy from anyone but, I'm 60 years old with a busted-up body from construction, my soon to be 90 year-old father is in a Nursing Home on Hospice, I'm the ONLY one dealing with his house, his bills, his meds, doing his laundry and everything about him. I run to the Nursing home sometimes twice a day, run to his house to collect bills then make sure they are correct and pay them and make sure no one broke into his house (lots of building/construction tools and materials). I also deal with my own house, bills etc-etc-etc and now this verry annoying Vette issue...and if, my Diesel Truck takes a crap I'm, screwed.
I only have a little bit of time to try to test this and that on the Vette in a 9' wide garage that I can't even open the doors all the way...I've been waiting for a fella I know to let me borrow his older Snap-On Brick Scanner and hoping he has the needed muiti-1 connector that will reach down into the ALDL. But it appears him getting back to me is not his priority....I'm mentally and physically drained.:bang
 

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This Car is wearing me down...not looking for a Pity Party or Sympathy from anyone but, I'm 60 years old with a busted-up body from construction, my soon to be 90 year-old father is in a Nursing Home on Hospice, I'm the ONLY one dealing with his house, his bills, his meds, doing his laundry and everything about him. I run to the Nursing home sometimes twice a day, run to his house to collect bills then make sure they are correct and pay them and make sure no one broke into his house (lots of building/construction tools and materials). I also deal with my own house, bills etc-etc-etc and now this verry annoying Vette issue...and if, my Diesel Truck takes a crap I'm, screwed.
I only have a little bit of time to try to test this and that on the Vette in a 9' wide garage that I can't even open the doors all the way...I've been waiting for a fella I know to let me borrow his older Snap-On Brick Scanner and hoping he has the needed muiti-1 connector that will reach down into the ALDL. But it appears him getting back to me is not his priority....I'm mentally and physically drained.:bang
Holley 4 bbl
770 Cfm Street Avenger.
Electric choke.
Be my choice.
 

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computer Q-jet

I think you've got a vacuum leak. I wouldn't even consider changing out the carb for a Holley. You'd have to run a carb adapter since the Holleys mentioned are square bore and will not fit on your manifold. YOu'd have to change everything on top of the engine before it's over.

Have you got a dwell meter at all or borrow one? Think of it as a duty cycle meter in this case. You need to know what the duty cycle is, that tells you what the computer is doing. To see if the MCS is working you can drop a little coffee stirrer straw in the bowl vent tube. you can see or feel it bouncing if the MCS is working.

Recall that the duty cycle is checked on the 6-cylinder on the meter.

IMO it's unlikely that something suddenly went wrong with the internals of the carb or the wiring harness to the computer.

Need to check throughly and carefully for a vacuum leak before launching off on a major repair that may not end well.

Tom
 
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