EGR ???

[92 LX]

Guys,
I searched to posts but I can't seem to find solutions to all my problems.
I'm getting some backfire thru the intake under part throttle, usually when it's cold but not always. The codes are: KOEO- 31 KOEO- 94,44,31. I've had the car for about six years now and when I bought it no "check engine" light was lit.
The previous owner removed a lot of the emissions stuff, smog pump, cats, EGR spacer, and maybe other stuff. I recently replaced the EGR valve which is bolted right up to the Cobra intake, and the vacuum port is plugged off. I think this may be part of the problem, but it was like that when I bought the car. These codes were taken after I replaced the expensive EGR. The '92 302 has a stock short block, j302 heads, Cobra intake, BBK 70mm TB, larger Mass Air meter, K&N, orange injectors (19s?), shorties, NEW Bosech O2s, 5 spd, 3:55s. Any ideas?

Many Thanks,
Frustrated,
Greg

 

[squeak93]

Do u still have the tubes that run to the back of ur heads?

 

[92 LX]

I don't know. I don't think so but I'll have to check. You said "the back" as in firewall side?

Thanks.

 

[92 LX]

squeak93 and others,
I checked and I do not have any pipes running to the back of my heads.
Any ideas?

Thanks,
Greg

 

[del.5.0 lx]

Guys,
I searched to posts but I can't seem to find solutions to all my problems.
I'm getting some backfire thru the intake under part throttle, usually when it's cold but not always. The codes are: KOEO- 31 KOEO- 94,44,31. I've had the car for about six years now and when I bought it no "check engine" light was lit.
The previous owner removed a lot of the emissions stuff, smog pump, cats, EGR spacer, and maybe other stuff. I recently replaced the EGR valve which is bolted right up to the Cobra intake, and the vacuum port is plugged off. I think this may be part of the problem, but it was like that when I bought the car. These codes were taken after I replaced the expensive EGR. The '92 302 has a stock short block, j302 heads, Cobra intake, BBK 70mm TB, larger Mass Air meter, K&N, orange injectors (19s?), shorties, NEW Bosech O2s, 5 spd, 3:55s. Any ideas?

Many Thanks,
Frustrated,
Greg

code koeo31 = EGR position sensing device is transmitting a voltage lower than the ECA expected to see durning the test
code 44=indcates the thermactor air system is not working.
code 94=e40Dapplications:refer to code 94 to a qualified transmission specialist or the dealer.
all other apps. indicates the side of the thermactor air system with cylinders 5 to 8 are not working
this info came from motorbooks workshop (how to tune and modify ford fuel injection

 

[92 LX]

Thanks guys,
Could this be why I sometimes get the backfire thru the intake?
Is there anyway to clear these codes permanently? a tweecer? Or should I just live with them? Will this cause my performance to suffer?
I don't understand how I could get these codes now since I didn't change anything (before I changed the EGR).

Greg

 

[joel5.0]

None of those codes will cause the symptom you are experiencing. Backfiring through the intake is usually a thirst for fuel, or valve timing problems. Have you checked fuel pressure?...... have you done a cylinders compression test?...... have you checked initial timing? ....LUK

 

[92 LX]

My fuel pressure runs around 40 psi. I did a compression test a few months ago and everything was fine. Timing, I haven't checked. I DID put some injector cleaner in the tank a few weeks ago and that seemed to help for a while and then it came back, but in the past few days (since I've filled up) it hasn't reocurred. Which makes me want to ask if it's time for new injectors? The car has almost 130K mi.
It does want to stall when I first start it in the morning, and runs a little sluggish until it warms up.

Thanks guys.

 

[67coupe]

Original fuel filter??? Cheap and easy to replace if it is.

I agree. The codes you listed should not cause the issue you desribe. Sounds more like a timing or fuel issue.

Edit: Might want to try a few free things, too. Reset idle and TPS per sticky (at top of forum). Clean MAF element with contact cleaner.

 

[92 LX]

No,
Recent fuel filter change. I'll check the other things. It seems to be behaving itself for now. I hope I'm not jinxing myself.

Thanks.
Can you guys think of any other problems with running my car with these codes? Performance? MILEAGE???

 

[joel5.0]

Well.... the EGR is automatically deleted by the EEC once it sees a failure, so the EGR induced spark adder is not applied. Other than an increase in the NOx emissions and emissions overall (thermactor system not working).......... nope, no performance or mileage problems should be experienced......

 

[RYC CUKR]

I had a similar problem once and it was the fuel pump. It showed good pressure at idle but when you would get on the throttle it just couldn't keep up.

If there was some way that you could temporarily mount a fuel pressure gauge where you could see it while you drive that would be ideal.

 

[92 LX]

Thanks for the tip. I remember the original owner told me he replaced the pump with a larger unit. It only backfired once since I put some Gummout injector cleaner in. I guess it could have been that? What is the life expectancy on injectors? Mine are about 130k old. Orange ones- 19psi????

Thanks guys

 

[92 LX]

Oh yea, I forgot to tell you. It runs real well under full throttle, I could have beat a vette this morn. but I let him go. I wish I could have seen his face when he saw the cop on the other side of the overpass!! I DID see major brake lights, and I'm sure he saw me laughing in his rear view mirror!!!

hee hee