PO118 frustratiom

[Chevyguy78]

If I take this one back it will be my 3rd one i've tried...

 

[withoutfear33]

try spraying the connection with electrical contact cleaner. may have gotten somthing on it that cant be seen.. ive also had this happen to me on my truck, sprayed down all the connections and never had a problem again.

 

[Chevyguy78]

I tried contact cleaner no worky. Next step is a hard reset on my ecu i will keep you posted.

 

[Chevyguy78]

Ok i got the code to go away, i had to do a hard reset on ecu. Now another issue ive been working on. Between 1200 and 1900 rpm's my truck is cutting out really bad. I know i have a tps (throttle position sencer) that is giving issues with my up shift at wot. Could it be that my tps is making my engine cut out? Or what else could it be?

 

[1LEG]

check Dist-cap and rotor. I had a MSD cap rotor and coil all go bad in less than a year or around 10000 miles. now i only buy AC delco from the dealer.

 

[Chevyguy78]

Im wondering if its a MAP sensor...

 

[Chevyguy78]

Update: I have been haveing an extremely hard time getting my truck to start lately so I went to do a full tune up on my truck this fine saturday evening and I came to notice something not quite right. A while back I did the intake gaskets and I took it to a local shop that usually does primo work to have my distrubitor reclocked one tooth because I didnt want to mess with it and to my suprise tonight the dist is loose. So now the timing is so far out of wack I cant even get it to idle. It will chug and die or pop and die. Im wondering if they just played with the timeing a little to try to compensate for the one tooth off and thats why its ran like crap since I did the gaskets.

So since my timing is all wacked out I know I need it on TDC on the compression stroke on the Number 1 cylinder. Now my question is How do I know im on the compression stroke and not the exhaust stroke? I hope some one can enlighten me on my next steps on how to finish this since im on the last step of this journey. Plus I was told that on these engines you need a digital timing light to adjust it. is this true or if you know something I dont please dont be afraide to chime in. Thanks in advance...

 

[90chevstepside]

Im no expert on this by any means, but I did intake gaskets in December. To tell the compression stroke and exhaust stroke apart, pull the #1 spark plug and put your thumb over the hole, have someone "bump" the key to try to start the truck. I mean bump it and immediately let go.. If you're on the compression stroke, you'll feel a good amount of pressure pushing your thumb out and it may even spray air out depending on how tight your thumb is on the hole, if it's exhaust, it will put pressure on your thumb trying to pull it into the block.

And yes, you need an electric timing light. Not sure if you know how to set timing, but you have to look at the pulley on the harmonic balancer and there's a small line in it going front to back, also, mounted to the block, there's a tab with small "pointers" on it that line up over that pulley. You want the line in the middle tick mark on the compression stroke, that is exactly TDC.


Put the line on that middle tick mark, then put the plug and wire back on. Be sure your distributor is just loose enough to be able to turn it some. Try cranking it.

It should either crank, backfire, or crank and cut up and spudded and smoke some. If it doesn't run just right, turn the distributor SLIGHTLY one way and try cranking again. If it didn't crank before and now it's cranking but rough running, you're going the right way. If it gets worse, you need to turn the distributor the other way.


I might be missing something so maybe someone else can chime in and help a little more, but thats a basic overview of the process and I hope it helps.


And don't forget to tighten down the distributor when you're done, otherwise you'll have to do it all again..

And thinking about it, they might have set the timing but not tightened down the distributor well and over time it worked loose a little, until it had enough slack to turn some.




It might be possible to tighten it down a little and play with the distributor to the left and right and get it back like it was bc even though it is loose, it's not loose enough to have jumped completely out of time to the point of resetting the timing. I would try tightening it a little and play with the timing to see if that fixes it before I went through the trouble of setting the timing and getting it to TDC.

 

[Chevyguy78]

I tried last night to get ittuned back in but all I could get it to do is run and smoke really bad. It was idleing but very rough. It was turned all the way one way and it didnt have any more slack to go any further to try to fine tune it. so I think it will just be easier to start over.

 

[Chevyguy78]

Ok so I finally got the truck to purr smoothly again! Full tune up, had the dist. Reclocked 1 tooth, cam retard set at 0degrees, and cat pulled off with an o2 simulater in place of last 02 sensor. She is running like a dream again. My fix it list is getting shorter atleast.