Idle Problem

[Rhaggz]

Hey guys, I am new here and I have a problem. My 68 coupe has a 91 Lincoln 5.0 EFI with an Edlebrock 5.0 Performer intake and an E-303 cam. My problem is that when the guy that put my engine together put the side plate on the plenum, he missed the bottom 2 bolts with the gasket and i just found it. Since it was built I had a cold idle problem, but fixing the gasket fixed that problem. Now, I have another problem, when I start the car it idles perfectly, however when i shift into gear it idles up and then quits. I have disconnected the battery to reset the computer, but it still does it.

Does anybody have any ideas on how to remedy the situation?

 

[stangg]

Which computer are you using? A9P or A9L? A9L is designed for manual trans. The A9P is designed for automatic transmissions, but will still work for a manual. But the A9L is not correct for an automatic from what I recall. I think it has something to do with anti stalling when slowing down though... it's been a while, so I can't say for sure.

 

[Rhaggz]

I think it is the A9P, it came out of the 91 Lincoln that the motor and AOD transmission came out of. I just pulled the positive side of the battery and left it off for a couple of hours and then reconnected it and started the car. It idles at between 750 and 900 RPM. is that normal? It still dies when I shift it into gear. Any help would be greatly appreciated... With these newer cars, I have no clue about how to work on them... I'm an old pre computer guy...

OH, You got a great looking ride!!!

 

[kb3]

Have you done a KOEO and KOER test to determine if all of your sensors are within proper tolerances? there is also a place to adjust the idle on the throttle body itself. One of the most likely candidates for trouble is the TPS on top of the throttle body. It has a fairly tight tolerance range.

 

[Rhaggz]

Have you done a KOEO and KOER test to determine if all of your sensors are within proper tolerances? there is also a place to adjust the idle on the throttle body itself. One of the most likely candidates for trouble is the TPS on top of the throttle body. It has a fairly tight tolerance range.

LOL... I have no idea even what that is, like I said in my previous post, I know nothing about these late model computerized varmints... But I will check it out and do so research to see what you are asking me... Thanks...

 

[AzPete]

Key On Engine Off
Key On Engine Running

Tests you do with a code reader for the vehicle the engine came out of. It will tell you what is wrong according to the codes it spits out.

 

[kb3]

LOL... I have no idea even what that is, like I said in my previous post, I know nothing about these late model computerized varmints... But I will check it out and do so research to see what you are asking me... Thanks...

Sorry...didn't mean to confuse you even more. Do a quick web search and you will find tons of info. One great website is www.oldfuelinjection.com. Specifically look at this link http://oldfuelinjection.com/?p=13 as it will show you how to do the tests, what the codes mean, etc. It is a basic, straightforward approach to get some self help.

 

[kb3]

Key On Engine Off
Key On Engine Running

Tests you do with a code reader for the vehicle the engine came out of. It will tell you what is wrong according to the codes it spits out.

although I know they may exist, the early SEFI 5.0 engines do not need or use a code reader. They use a check engine light or you can use a multimeter or test light to get "flashing" codes

 

[Rhaggz]

OK guys I understand what your saying, however there are no check engine lights the engine is now in a 68 Mustang coupe with no idiot lights at all... I think the computer is behind the glove box, but there are no ports to connect anything to. I planned on pulling the glove box this afternoon, but we have had some pretty good storms so I put it off until tomorrow if the storms stay away... I'm not sure if there is some kind of pigtail or what that I need to connect a code reader or voltmeter... LOL I'm sorry guys, I'm sure most of you guys think I'm nuts or something but I wanted a classic that was updated so I could drive it anywhere and something the wife could drive without worrying about an old motor dying... So much for that idea... Otherwise I would have stayed with a carbed 289 or maybe a 351...

 

[kb3]

OK guys I understand what your saying, however there are no check engine lights the engine is now in a 68 Mustang coupe with no idiot lights at all... I think the computer is behind the glove box, but there are no ports to connect anything to. I planned on pulling the glove box this afternoon, but we have had some pretty good storms so I put it off until tomorrow if the storms stay away... I'm not sure if there is some kind of pigtail or what that I need to connect a code reader or voltmeter... LOL I'm sorry guys, I'm sure most of you guys think I'm nuts or something but I wanted a classic that was updated so I could drive it anywhere and something the wife could drive without worrying about an old motor dying... So much for that idea... Otherwise I would have stayed with a carbed 289 or maybe a 351...

I don't think you are nuts...you are right where I was just a couple of months ago! I did quite a bit of research and learned more than I ever wanted to know. Assuming the 91 Lincoln is just like the 87-93 Ford 5.0 you should have a pigtail in the engine compartment similar to this one http://oldfuelinjection.com/images/selftest01.gif It may take some searching to find it, but it is part of the original engine harness you should be currently using on your 5.0 If you follow the steps on that website it shows you right where to plug in the test prongs. I installed a small LED light in the glove box to act as a check engine light, again you don't have to have that, just use a test light in the plug above. I would be happy to talk you you a bit more if you need help. Let me know and I can pass on my number to you.

Ken

 

[66gt350]

although I know they may exist, the early SEFI 5.0 engines do not need or use a code reader. They use a check engine light or you can use a multimeter or test light to get "flashing" codes

I've got a code reader for my efi conversion...it's easier to read a number on a display than to count the flashes.

By side plate on the plenum...do you mean where the egr bolts to??

 

[kb3]

I've got a code reader for my efi conversion...it's easier to read a number on a display than to count the flashes.

By side plate on the plenum...do you mean where the egr bolts to??

and to piggy back on this...if the EGR was removed and blocked off, you also need to add a EGR elimator plug to the harness or the computer will be looking for something that is not there. This seems to be a common mistake people have made when fitting these 5.0s into other cars.

 

[Rhaggz]

I don't think you are nuts...you are right where I was just a couple of months ago! I did quite a bit of research and learned more than I ever wanted to know. Assuming the 91 Lincoln is just like the 87-93 Ford 5.0 you should have a pigtail in the engine compartment similar to this one http://oldfuelinjection.com/images/selftest01.gif It may take some searching to find it, but it is part of the original engine harness you should be currently using on your 5.0 If you follow the steps on that website it shows you right where to plug in the test prongs. I installed a small LED light in the glove box to act as a check engine light, again you don't have to have that, just use a test light in the plug above. I would be happy to talk you you a bit more if you need help. Let me know and I can pass on my number to you.

Ken

Here is a picture of the side plate I was referring to... The conversion was done with a Painless wiring harness so there are no plugs... The main harness runs through the firewall right behind the glovebox. I have a LED light i can install if I can just figure out where to plug it in.

 

[kb3]

that is just an access plate to the plenum...if it wasn't sealed you would have a nasty vacuum leak. I do see the EGR valve, so you are good there. Is the engine harness from Painless or was the engine harness tied into a Painless chassis harness?

 

[Rhaggz]

Yeah that was the problem, I had a vacuum leak and I fixed it... that fixed the cold idle problem I had but created the no ideal in gear problem. the painless harness is just for the computer. Everything else is the stock original wiring.

 

[kb3]

The Painless harness came with a provision for a check engine light. It may be buried under the dash or never plugged in. Look here http://www.painlessperformance.com/Manuals/60510.pdf (page 7 of the manual) I just plugged a simple Radio Shack LED into the harness I bought and mounted it in the glove box. Once you have the light, you can easily run the tests, although you will still need to located the plug I pointed out earlier which Painless also supplied (page 20 of the manual)

 

[stangg]

Is your throttle position sensor set correctly? Another thought... with an automatic, are there any sensors that should be feeding the computer to let it know when it's in drive?

And just for reference... years ago I had a T bird that was giving me acceleration problems... we disconnected the MAF sensor to see if it ran any different and to our surprise it ran very well. We put a new MAF sensor in and it was back to normal power. Might be woth a shot to see if you unplug the MAF for a minute or two to see if it holds the idle in gear.

 

[Sluggo]

Did you have the air intake hose off while you were fixing the intake?

Sounds like the intake hose is opening up somewhere when the motor torques when put in gear.

Make sure the hose did not crack somewhere between the bellows.

I have not messed with a 5.0 of that era but if the intake air temp and volume are being measured near the air cleaner, any unmetered air coming in between the sensor and the throttle body will cause a stall.

 

[AzPete]

Could it be a converter issue in the tranny....locked up and not releasing..........