My truck has been cutting out and stalling. So I figured it probably needs a tuneup since it has been 75000 miles since the last one. I changed the sparks, wires, rotor and cap. It ran magnificent for about two hours. Then it started cutting out even worse than before the tune up. So I timmed it. No change. So I did the paper clip code check. Wow is that easy. If only everybody knew how easy that is.

So here are the codes I got doing it three times. 67 67 29 32

Speed sensor
EVP

What would you experts suggest me do next?

Thank you!

 

Neither of those codes should prevent it from at least idling. I would make sure the fuel system isn't meesing up, change the fuel filter and check pressure at the rail as the pump may be going out.

 

I changed the fuel filter with the tuneup It idles and has only stalled twice. When I sit at a red light the RPM's are jumping all over the place. i do believe you when you say the fuel filter may be going out. That was my first thought. Should I ignore the codes Would any of those sensors make it run so poor that it is jerking you all over the street. It revs up then it drops, then it just cuts out like its runing on two cylenders. Then it runs perfect, then it start to cut out. It is so sporatic. Any body else got any ideas?

 

check fuel pressure at the rail with a gauge.

the coil may be bad or going bad also. Also do you notice this behavior more whent he engine is up to operating temps? if so it may be a bad TFI module. this is the plastic deal bolted to the side of the distributor.

when you checked the timing what was it set at and was the spout connector removed?

 

Yes spout connecter remove. It was right at 15 degrees so I moved it to about 12-13. You guys are starting to make me feel like the codes mean nothing. When I first asked this question a month ago...everyone said pull the codes. Now I pull the codes and everybody seems to be making guesses. Do the codes mean anything or should I just start replacing things?

 

I will check the fuel pressure tonight. I noticed the cap on the fuel rail, it looked like a tire valve stem. What should I use to check the pressure and what should the pressure be set at? Can I use a tire gauge??? LOL

 

I can't remember what the pressure is right off the top of my head, I wanna say 39 lbs, i swear its *9 something.

The VSS affect shifting and speedometer
EVP will affect MPG but shouldn't affect engine operation that much.

Pulling the codes is a very important step but those particular coeds shouldn't be causing your issue, so we are ignoring them for right now.

Ha I was right! by the way here is a link thatll explain the fuel pressure testing better and shows the proper tool

http://fordfuelinjection.com/?p=41

 

15 degrees is way too much.. I could set mine to 15+, but I had a worn timing chain (200k miles), it wouldn't even run at 10degrees.. after I changed out my chain, I knock at even 12 degrees.

and the thing with codes, they ARE important and most of the time you can troubleshoot with just codes.. however, a lot of times on a truck this old, you can't. You have to do a bit of good old fashion part testing AND run codes on early EFI. I have a 1990 so I know how it is, codes help sometimes, but sometimes they don't.. it's always the first place you wanna look though.


anyways, change your speed sensor, it's the one in the transfer case NOT the rear axle. I'd also check to make sure your EGR diaphragm isn't shot and that all vacuum lines are plugged in, a vacuum leak might cause this issue, an EGR being stuck open might also cause this issue and the EVP error can be thrown if your EGR valve is screwy and/or there is a vacuum leak.

 

Lets do these in numerical order shall we?

Code 29 - Indicates that the VSS (Vehicle Speed Sensor was NOT sending signal to the ECM. This WILL cause the ECM to go into "limp mode" causing significant performance issues. Its not going to LET you "hurt" the truck in "limp mode" but it will reduce performance settings to the bare minimum to get you home. But if the ECM is dropping into "limp mode" it will definitely feel like the engine is cutting out because the ECM is basically reducing engine power to a bare minimum so you can "limp" home without risking damage to anything critical until you can get it fixed.

Troubleshoot by disconnecting and removing the VSS from the top of the rear differential housing. Wipe the end that goes into the the diff. with a lint-free cloth. Inspect the connector both on the sensor AND the harness. Clean the contacts as best you can and repack the female connector with dielectric grease before reconnecting. Clear Codes and start the truck. Put the transmission in 1 (low) and accelerate to 25 mph then let it COAST to a stop. Seriously, let it coast. Run the KOEO test again and see if Code 29 rears its ugly head again. If it does, you need to dig deeper into the harness and check for damaged wiring between the VSS and the ECM.

Code 32 - Indicates that either EGR valve was not seated OR the EVP sensor has failed.

Troubleshoot Code 32 by checking the condition of the pintle inside the EGR valve. Its hard to see clearly but a flashlight through the holes in the side will let you see if the valve is truly seating or not. If it is NOT seating, apply vacuum to the valve (about 8-10 Hg or just get a clean length of vacuum line and suck on it). Release the vacuum quickly. If it reseats, it probably just needs a good cleaning. Good ol' fashion pipe cleaners work best. Take care not to puncture the diaphragm just above the pintle or you will be replacing the entire valve.

In the event the valve IS working properly, check the connection at the EVP sensor atop the EGR valve. If the connection is good and no corrosion is present, its most likely time to replace the EVP sensor.

Code 67 - In an E4OD-equipped truck this Code indicates one of two possible issues. The MLPS (Manual Lever Position Sensor is out of adjustment (sending the wrong voltage back to the ECM) or the guy performing the diagnostic tests didn't shut of the A/C compressor while he ran the tests. (Hint... the latter is operator error).

In the event the MLPS is out of adjustment (or the shift linkage is really sloppy and causing a misalignment) you can troubleshoot Code 67 by tightening up the shift linkage if its loose. And check the MLPS (mounted to the side of the transmission where the linkage attaches) for physical damage and electrical connection issues.

Something to consider in this situation is the fact that you have a problem with the two most critical sensors for the harmonious operation of the engine and transmission as a unit. If the VSS signal is lost the ECM drops into "limp mode" HOWEVER, if the ECM "thinks" the transmission is in a "moving" gear when its NOT, then it is "looking" for VSS signal when there really shouldn't be any. Its a Catch 22 situation. My suggestion is to make absolutely certain the MLPS is functioning and aligned properly so its sending the right signal to the ECM. If this issue is resolved, clear Codes and see if Code 29 returns before assuming there is really something wrong other than an MLSP issue.

BTW, I've never run base timing any higher than 11º BTDC. Further than that and not only do you get the serious detonation others have talked about but it doesn't gain you a blessed thing.

 

grey, i've mentioned it a dozen times across multiple threads, I have a theory to the timing increase people do.. even though ignition to crank timing is different than valve to crank, I think it's a slack chain that allows the bump to 14+ degrees with nothing but performance increases.
Before I changed my timing chain, I could NOT run right at 10degrees, I would get backfires through my intake, it would run decently at 12 degrees but best at like 14 or so.. after the chain replacement swap, 10-11 is the sweet spot.

Bottom line, I think your timing chain stretches so much that it retards valve to crank timing and the bump in ignition timing helps offset the issue a tad. I definitely recommend the timing bump as long as there is no knocking, but only as a temporary bandaid, as eventually you're going to wish you had changed that timing chain sooner than later.

edit:

Oh, I can unplug the MLPS, VSS and EVP *after* the truck is started and it will run okay, nothing like his problems.. my VSS did break at one point and I think it was causing lunging, like TC lock and unlock randomly, but someone else on here told me it wasn't possible. If they were wrong and it is possible for VSS to cause random lock/unlock at the TC, then it could definitely cause a surging idle and stalling out.

cutting out could be anything.. if it were my truck, immediately Id clean my IAC and throttle body, change fuel filter (done already though) uh.. is your MAP sensor okay? I once spent 3 days trying to find the source of my truck randomly cutting out, it ended up being a bad ground cable. Again, if your EGR valve is stuck open or tore it will cause drivability problems and they will seem completely random.

seriously, you ran KOEO, KOER and CM, what seperate codes for each? KOEO will tell us if a sensor is flat out broken or unplugged, KOER will tell us a sensor isn't working while running under KOER conditions, then CM will show us all codes that have happened, probably intermittantly under conditions not tested during KOER.

 

Wow you guys gave me a butt load of information. After hearing Greystreaks answer it reminds me to tell you guys I had the C6 transmission rebuilt and the transfercase rebuilt about two months ago. Eversince it came out of the shop I noticed my seedo acting up (jumping) and it was shifting differently than before. Kinda hard. Does this information help you guys in pin pointing what may have happen?

 

well since you have a C6 it uses a vacum modulator to control shifting and such. if those lines are cracked it could cause erratic engine due to the leak and also affect how the tranny shifts.

 

Was the E4OD the original transmission or a swap? If so, was the ECM swapped at the time of the trans swap and what ECM was used? Code 67 has at least three different meanings but it is dependent upon how the vehicles was equipped originally. If swaps were made after the fact, Code 67 may be completely anomalous.

 

No the C6 was the origional trans, now swap, just rebuilt.

 

There should not be a vss on this truck the Speedo is MECHANICAL. I Have a 89 also the codes could be a side effect of the condition and may mean nothing at this point. When does it stall: running down the road, idling at a stoplight, randomly? There are a few ways to go. fuel pumps there are 2 if the low pressure one drops out you can run but it will eventually vapor lock and stall or at least mine did. Ignition could be another issue, The ECM could be having problem with a bad ground our connection for that matter which would be sending erratic signals.