Well the truck is supposedly fixed. They replaced the ground wire in the circuit that includes the 02 sensor, cruse control and some other things. I don’t know what all is on that circuit but they said that I will notice that some other things will work better now also. The owner drove the truck in the rain on Saturday and it ran great. He told me he wants to drive it today in the dry to be sure it is ok. So, I am picking it up tonight and will drive it the rest of the week and see how it goes. I am not getting my hopes up till I drive it for awhile. Wow, I hope this is the end to this saga. I will post the results of the driving at the end of the week.

Todd

 

Glad you've got it back finally. Hope it's fixed this time.

 

bad grounds can cause a multitude of problems.

 

Well I picked up the truck. I put $20 (8) gallons of gas in it and after 60 miles I needed gas again. So I am still getting about 7 - 8 MPG. The truck now starts hard and has a big lack of power. Oh, and by the way, it is still shutting off, (bucking). $515 dollars later and it is back in the garage. I'll tell you, I am about to the end of the line with it. I'm leaving tomorrow for the mountains and coming back next Wednesday. If it isn't fixed I may just go truck hunting. Dam thing.

Todd

 

I dont think replacing that O2 wire will help the bucking and jumping but it could help the fuel usage. the bucking and jumping is like something shutting on and off. such as DFR, ignition control, fuel pump, trash in fuel line, little relays with loose connection. My DFR made mine buck and jump, loose little relay socket made it not start or turn on fuel pumps. The relay tested good but the socket had a loose connection. I assume you still have no trouble codes showing?

I even found out something I had been wrong about. THe IAC or idle air bypass valve does operate at any engine speed. The computer can vary the voltage to the valve to partially open or close it. Therefore it can affect fuel use and power to some degree. I havent read much about it yet as i just got the book a few days ago. Like yours my 87 fuel usge is the pits. Im down to about 13 mpg instead of 16 to 18..

 

Hello All,

Back from the mountians. I stopped at the garage yesterday to check on the truck. The timming chain has 10 degrees of slack in it. This was checked and noted some time back. So he changed the timing 10 degrees and I took it for a drive. It does run better but still not perfect. I guess the reman motor had a junk chain put on it. 19000 miles and it needs a chain. So that is the next step in the saga. I'll put a good chain on it and get the timing back where it should be and we'll see what that does. He seems to think that will make it run really good after that is fixed. It does have a lot more power with the timing bumped up. That's all for now. I'm not sure when I will get the time top change the chain but I will update when I do. It is deer season and I am going to hunt for awhile.

Will it hurt anything to drive it like that for awhile till I get time to change it??

Todd

 

well if the timing chain has slack it could break.
Im not sure if ur engine is an interference engine or not but if it is and the timing chain goes belly up then you will be out an engine you just spent all that time tryin to fix
BTW congratz on gettin ur truck fixed (hopefully)

 

10 deg of slack in the timing chain is way to much , replace the chain & set the timing end of problem ....Lew

 

That's next. It may be a few weeks till I get it done. I will update everyone when I change out the chain and see if that fixes it.

Todd

 

oops sorry .......how do you delete a post?

 

I had a FPR fail and fuel was sucked into the motor thru the Vacuum line.
Check the regulator as mentioned above.

 

ten degrees off on timing could cause bucking and lack of power. Dont know for sure but i would think the computer would turn off the firing pulse or fuel injectors if the timing went out of the min and max limits.

 

He has checked the FPR and replaced it twice

 

yep, about the only part he hasn't replaced is the dual fuel reservoir (DFR),engine and transmission. and he tested the DFR by bypassing it and running on one tank. computer, spark plugs, and O2 sensor was replaced twice too if I remember correctly. When you get right down to it the engine or enjectors are about the only thing left.

 

I believe he did tests to see if the injectors were the problem and they weren't.

And the Engine is a reman with about 20,000 on it (if i remember correctly)