code 31-egr sensor and valve ?'s
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code 31-egr sensor and valve ?'s
Ok now for my next mission. I pulled the codes on my 1986 f-250 5.0 l EFI and get the code reading 31 which tells me that the egr sensor is below miniumn voltage. OR EGR VALVE is bad. So i buy a new 1 and install them, Now i do not get the code 31. The truck runs very well when cold, But once it is up to normal operating temp she bucks and misses really bad. I have installed new plugs, wires, rotor, cap, fuel filter, air filter. What may be causing this to happen. What would be a good starting point to troubleshoot this down ?
thx
Joe
thx
Joe
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code 31-egr sensor and valve ?'s
Did you replace the selonoid too? When I replaced my EGR valve I was told to replace the selonoid as well because they usually go in pairs. I dont know if this is the problem, just a tip that I hope will help.
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code 31-egr sensor and valve ?'s
You need to narrow it down a little more by doing some testing. I am assuming you are getting code 11 (all good).
After it warms up it idles good?(if yes, then no vacuum leaks)
Does it run down the road ok but bucks and jerks on acceleration and hills only?(if yes, may be a fuel delivery problem)
After it warms up it idles good?(if yes, then no vacuum leaks)
Does it run down the road ok but bucks and jerks on acceleration and hills only?(if yes, may be a fuel delivery problem)
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code 31-egr sensor and valve ?'s
Yes that is correct i am getting code 11= all good
It will run smoothas can be at a cold or warm idle
It runs down the road good and smooth, BUT begins to jerk and bucks like a bull on acceleration, Hills do seem to make it a little worse of a problem.
It will run smoothas can be at a cold or warm idle
It runs down the road good and smooth, BUT begins to jerk and bucks like a bull on acceleration, Hills do seem to make it a little worse of a problem.
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code 31-egr sensor and valve ?'s
It's probably going to be a basic fuel or spark problem. If it was a sensor, we can assume the computer would have caught it and given an error code.
If you had a fuel pressure guage, you could hook it to the fuel rail and see if the pressure was ok when the problem happened.
If you can't check the fuel pressure, you can take a guess that it may be spark related. A good guess to what is causing the problem would be the TFI module on the side of the distributor. This module could make the engine cut out, and is known to have problems with heat.
I hate guessing, because it wastes money. But in some cases you have to.
If you had a fuel pressure guage, you could hook it to the fuel rail and see if the pressure was ok when the problem happened.
If you can't check the fuel pressure, you can take a guess that it may be spark related. A good guess to what is causing the problem would be the TFI module on the side of the distributor. This module could make the engine cut out, and is known to have problems with heat.
I hate guessing, because it wastes money. But in some cases you have to.
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code 31-egr sensor and valve ?'s
Here's a couple more guesses. (1) Is the SPOUT connector connected? (2) This could also be a faulty TPS, even though a code is not present. The TPS is easy to test with a voltmeter.....
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code 31-egr sensor and valve ?'s
[QUOTE]Originally posted by franklin2
[B]It's probably going to be a basic fuel or spark problem. If it was a sensor, we can assume the computer would have caught it and given an error code.
If you had a fuel pressure guage, you could hook it to the fuel rail and see if the pressure was ok when the problem happened.
If you can't check the fuel pressure, you can take a guess that it may be spark related. A good guess to what is causing the problem would be the TFI module on the side of the distributor. This module could make the engine cut out, and is known to have problems with heat.
Is there anyway to check the TFI module ?
[B]It's probably going to be a basic fuel or spark problem. If it was a sensor, we can assume the computer would have caught it and given an error code.
If you had a fuel pressure guage, you could hook it to the fuel rail and see if the pressure was ok when the problem happened.
If you can't check the fuel pressure, you can take a guess that it may be spark related. A good guess to what is causing the problem would be the TFI module on the side of the distributor. This module could make the engine cut out, and is known to have problems with heat.
Is there anyway to check the TFI module ?
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code 31-egr sensor and valve ?'s
Originally posted by thelonerangerxlt
Here's a couple more guesses. (1) Is the SPOUT connector connected? (2) This could also be a faulty TPS, even though a code is not present. The TPS is easy to test with a voltmeter.....
Here's a couple more guesses. (1) Is the SPOUT connector connected? (2) This could also be a faulty TPS, even though a code is not present. The TPS is easy to test with a voltmeter.....
what is the testing procedure for the TPS , Where is it located ?
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code 31-egr sensor and valve ?'s
Oldford, the SPOUT (SPark OUTput) connector is a plug in the wiring harness, close to the distributor. It is what is disconnected when the timing is set. It's doubtful that your's is loose, I just wanted to cover all bases.
The TPS is bolted onto the throttle body, and is basically a variable resistor. It is a small black plastic sensor, that has a wiring harness coming out of it with three wires. One wire is ground, one is reference voltage (I believe around 5v), and the other is the signal wire. With the key on, you will have to backprobe the wires to determine which is the signal wire. The signal wire should read about .8v with the throttle closed, and gradually increase to about 4v at wide open throttle. The voltage increase should be smooth. If it is erratic, the TPS is worn out.
Just to add more to the mix
, it could also be a dirty MAF sensor. You can do a search to find cleaning procedures. (BTW, a dirty MAF won't trigger a code either, but will give driveability problems.
Did the bucking start EXACTLY the same time as the EGR parts replacement?
The TPS is bolted onto the throttle body, and is basically a variable resistor. It is a small black plastic sensor, that has a wiring harness coming out of it with three wires. One wire is ground, one is reference voltage (I believe around 5v), and the other is the signal wire. With the key on, you will have to backprobe the wires to determine which is the signal wire. The signal wire should read about .8v with the throttle closed, and gradually increase to about 4v at wide open throttle. The voltage increase should be smooth. If it is erratic, the TPS is worn out.
Just to add more to the mix
, it could also be a dirty MAF sensor. You can do a search to find cleaning procedures. (BTW, a dirty MAF won't trigger a code either, but will give driveability problems.Did the bucking start EXACTLY the same time as the EGR parts replacement?
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code 31-egr sensor and valve ?'s
Okie dokie, I WILL CHECK what you two have suggested i try, and get back with you when i get all testing done. Again
Thank-you for the pointers in the right direction
Joe
Thank-you for the pointers in the right direction
Joe