Well, I hook up the code scanner tonight. I did the Key On Engine Off (KOEO) test and the Key On Engine Running (KOER) test.

For the KOEO test it gave me a system pass code for the test and then for the continuous memory code it gave me a 32 for

"EGR valve position (EVP) sensor or pressure feedback EGR (PFE) sensor - signal voltage is below closed limit or has gone boyond its set limits or Problems with EGR valve controlling."


For the KOER test it gave me a 44 for

"Problems in Thermactor Air Control system."


From what I read, the Thermactor Air Control system aids in burning unused fuel in the exhaust and exhaust warm up. Would this really be the cause? The KOEO continuous memory code for the EGR sensors is supposed to be from a possible past repair. Could the EGR cause this? I thought someone mentioned that before.[sm=smiley25.gif]

 

I cleared the codes last week to see if something new/different would show up after driving a while. I put a new air filter in and changed the oil last night. I also added some compression booster to the oil to try to rule out lack of compression. It runs like it has a new air filter and an oil change, but still shakes. I'll see what codes I get on it tonight. I may also buy a compression tester to see what I get from that test. I also put two cans of Sea Foam in the tank on my last fill up, but so far only minor (if any) improvement. I may just go to a junk yard and see if I can get an EGR valve and fuel injectors cheap to see if they make a change. If they do, I'll buy new ones. If they don't, I'll put the old ones back in.

Would a bad catalitic convertor cause this? If there is something that is restricting the flow in the cat, it may act funny at low rpm.

 

Not going back and read this again so, didn't you do a compressure test on all the cyl.? If so did you find any with low compression? Plus a bad cyl. would shake bad at idle too. [sm=chattypair.gif]

 

Yea a sticking EGR valve would give you a shake , rough Idle ,,, A dead Cyl , A vac leak , A bad cam lobe ,Normally if you got a bad CAT , it will have no power , wouldnt like to go over 40 MPH,( Compression Booster ???? ) With the Engine running if you short out each cylinder one at a time can you tell which cylinder does not make a change with it shorted out ???? if so thats probaly your problem cyl ..( Compression Booster ??? )--We use send NEW guys down to the parts store to pick up a can of Compression cause we would have a cyl that we told him was low, The parts guy would send him to another store , Finally one guy would give him a can of Motor Honey an ring it up,,, Tell him it was $300.00 cash,, So of course he would have to call the shop , An Hear all of us LAUGHING in the background !!!![sm=icon_cheers.gif]

 

I called it compression booster because I can't think of what the heck it's called. You add it to your oil if you have rings that are going bad and it is supposed to help compression loss. It comes in a bottle that is about half a quart, and it is a really thick liquid.

Anyway...[sm=alcoholic.gif]

 

I know I'm moving along quite slow with this, but after clearing the codes and running for a while I checked the codes again. It is giving me another ERG related code. I still have yet to do compression tests on it, but I will keep posting my results as I SLOWLY make progress.

 

I finally did compression tests on my engine last night. I found one cylinder (naturally the last one) that had low/bad compression. It happens to be the same one that I thought might be having issues when I pulled the plug wires off one at a time while the engine was running to listen for a change in idle (back in August - yes, I'm slow). When I pulled the plug out to do the compression test, it was still wet with fuel. The cylinder isn't able to create enough compression at low rpm to allow for a good explosion, which is no doubt causing the shaking. Now the question is do I have a bad valve, cam, or other? I'm scheduled to bring it in to a repair/service center this coming Tuesday, so I'll let them figure it out. I will let everyone know what is found, and how much t will cost.

 

Change of plans. I called a local salvage yard and was able to find a cylinder head assembly with valves, springs, and all from a working engine for $45. I am going to replace it myself over the Thanks Giving break, and while I'm at it I'll replace both head gaskets and intake gaskets for good measure. I'll keep everyone informed...

I also heard that these heads have a tendency to warp. Is that true? Has anyone else heard of that?

 

Changed the head out. It works great now in the city, but if I take it out on the highway is starts running poorly. I'll be driving on the highway for 10 minutes just fine, and then it starts acting like it is missing or not getting fuel or something. Then after that it shakes and runs poorly at low speeds, too. I'll turn it off and let it sit, start it up, and it will drive fine again... Until I get on the highway for 10 min or so again. What now? Any thoughts, PLEASE?!

 

Alright...

I want to try to put a different spin on this issue. As I was thinking about the issue I am currently having, I remembered that it started to do this sputtering and missing even before I changed out the head and the gaskets, so I don't think that the issues are related. I drove it again last night and it started fine, ran through the city fine, and then started to accelerate hard around 55mph as I got on the high way. It ran O.K. on the highway as long as I wasn't accelerating. When I accelerate, it starts to sputter and miss. If I hold the speed w/ cruise control, it seems O.K. Exiting the highway was the same thing; it ran rough and missed. But as I drove though the city after exiting the highway it eventually began to clear up. I'm starting to wonder if my exhaust system is partially clogged. I had seven working cylinder before and it started to do this, and now I have eight - more exhaust. It begins to do this at higher speeds, and therefore higher rpm - more exhaust. I also had to move the exhaust manifolds to remove the heads, which could have knocked something loose to restrict the passage more. I notice too that when I start it on cold days and let it warm up a bit before I take off that there is exhaust coming up from the area under the cab, so I know my exhaust isn't in the best condition to begin with.

Any other thoughts or input would be greatly appreciated!
[sm=wtf.gif]