Had the heads off. Replaced head gaskets, intake gasket, and so on. Ran okay for about two miles. Started to spit and sputter and then it would run okay, spit and sputter, run okay. Took back to mechanic. Replaced air charge temp. sensor, coolant temp. sensor, (not temp. guage sensor), different injectors from another running engine, and plugs. Still same problem. Checked timing, a little off, set it to correct timing. Problem went away but power was lacking. Ran okay for two weeks and now today without warning same problem. The tail pipe is as black as coal with soot. Hold the gas pedal at same position, same rpm and it sputters horibly, then all of a sudden it will smooth out and run like a champ. It will do this until you shut it off. Restart it and it will run okay for a couple of minutes and start acting up again.While going down the road when it starts to act up going full throttle will smooth the engine out but lacks power. Any guesses? I am starting to get pretty P.O.'d. Going to try to pull codes myself in the morning before I call the machanic.

 

Check the wiring for the O2, its gets burnt easy, should give you a code but you never know. Also check for gas in the vacuum line for the fuel pressure regulator after running it and test fuel pressure.

 

Update. Got in the vehicle today, started up and ran without a miss, drove 12 miles to work. Hopefully not busy today, going for some codes. Still seems to lack some power.

 

When you set the timing, did you have the SPOUT disconnected?

 

Yes. Set timing to 10btc. Plugged the spout back in and it went to about 24 if I remember right.

 

Sorry I had to ask, but it's such a common mistake. In that case, I'll wait and see what you get from the self-tests.

 

Okay, here we go with the codes. They might as well be French to me. KOEO; code 33, EGR valve opening not detected, code 41 no HEGO switch detected, code 54 ACT indicated -40F/circuit open, code 63 TP circuit below minimum voltage. KOER; code 25 (I thought) could be 26, code 33 EGR valve opening not detected, code 41 HEGO sensor circuit indicates system lean, code 74 brake on/off (BOO) circuit failure/not actuated during self test. HELP.

 

I think the first set of codes are continuous codes not KOEO codes so skip them for now and do the KOER.

I'm not familar with the 33 (EGR) so I'll let mrshorty take that one, the 41 sounds like bad wiring, exhaust leak near the the O2 or bad O2. Did you hit the brake pedal after the ID code for the 74. Almost forgot the 25, it's the knock sensor, again I never had to deal with that on my 1989.

Now for the others, skip the 33 and 41 until you clear the KOER. 54 might be bad wiring or connection for the ACT. For the 63 I would again check the wiring and make sure the resistance of the TPS is smooth.

If you would like a copy of any of the pinpoint tests drop me an email and remind me about your codes and truck.

 

I've never had to deal with an EGR code on my truck, either. Do you know how to tell a KOEO from a continuous memory code? If so, then ignore the next few sentences.
The KOEO test will proceed as follows:
1) Fast codes (ignore)
2) KOEO hard fault (aka KOEO) codes. 11 indicates "pass." Did you get a pass code here?
3) separator pulse. some code readers output "10"
4) continuous memory codes.

EGR codes can either be an electrical fault or mechanical. It seems they are usually electrical, so be sure to diagnose the circuit before buying an EGR valve. Get the pinpoint test from Ken00 so you can work through the circuit systematically. Also be sure to positively identify which kind of code it is. A KOEO code almost certainly means it's an electrical fault. One interesting thing I note is that, not only do you have an EGR code, but you also have a TPS code and an IAT code. All three of these sensors are "powered" by the computer's "Vref" -- a steady 5 V signal that the computer uses as a reference voltage for these and other sensors. May be worth investigating.

As noted, the KOER 74 is almost always from not pressing the brake after the engine id is output.

The only time I've seen a 25 was when I didn't "goose" the throttle hard enough for the dynamic respone test. Be sure, when the "goose" pulse is received not to be half-hearted in goosing the throttle. Give it an assertive 3/4 to full throttle "goose".

 

I was checking the wires for the O2 sensor and found an orange wire with a crimp on ring. The wire runs in the loom that comes up the back of the engine and across the top of the engine on the pass. side. I would assume that this is a ground. I has not been unhooked that long, you can see shiny metal on the ring were it was under a bolt. Trace the wire to the front of the engine and loose it in all the wire. This wire starts on top somewhere and end at the back of the engine, about 1/3 of the way down from the top. Any idea what that wire is? Also been thinking about the codes some more. A few months ago I heard a hissing sound from the pass. side when I parked the vehicle. Looking at the EGR system, it has a vacuum line that run to a solenoid, could that be leaking. Have not heard it in a while, maybe that is also my slight ruff idle. Have not had a chance to do the pinpoint test. Might take a day or two to get to it. Not sputtering today.

 

Can't help with the orange wire, the diagrams are different from the 1989 and that what I have. I f you think you have a vacuum leak I would address that before doing anything else, other than that wire. I was helping a guy with a 2.3 Ranger a few weeks back and the EVP is a very common problem if you have one on your truck.

 

Think I have one problem traced to the egr valve vaccum solenoid. Not getting vacuum to egr valve, no matter what rpm. Lines are good. I have vaccum to solenoid but nothing coming out. Does anybody know the voltage I should have at the solenoid plug and which wire to check, one yellow one red. Also the low on power issue. The vaccum guage has a lables on it, when at idle it reads about 15 in. and say slow timing. Is this correct? What should the vacuum read? Taking reading from the ports on the plenum. Should I wait to fix the egr problem before I set the timing?

 

Get a wiring diagram. That red wire comes off of the EEC relay, and a DVOM should show 12 V between that wire and ground when the key is on. The other wire leads to the PCM, which acts as a ground side switch to open and close the solenoid. A quick test of the solenoid operation can be performed by entering the output state test (just after the continuous memory codes are output in the KOEO test). Once you've entered this test mode, pressing the throttle should cycle the various solenoids (including the EGR solenoid) on-off then off-on.