WeGotMud

Projects & Parts => Garage/Tech => Topic started by: J.C. on March 31, 2014, 11:10:48 PM

Title: tbi troubles
Post by: J.C. on March 31, 2014, 11:10:48 PM
I have an 88 chevy and a 91 gmc. Both 350 tbi's. I replaced the distributor on the 91. I retimed it to zero degrees with wire unplugged. Now I'm getting knock sensor code 43. I've researched it on Google and now I'm here. I tried a new esc module, but not much has changed. Can't get the truck out of the driveway when test driving it because It pops through intake and exhaust. Before I did the distributor, it ran decent. Not sure how changing that would make it knock, especially if nothing has changed...

Any clues?
Title: Re: tbi troubles
Post by: lilred on March 31, 2014, 11:40:19 PM
wiggle your injector plug ins. They run like p00 on one injector lol
Title: Re: tbi troubles
Post by: xjs3667 on March 31, 2014, 11:54:52 PM
Map sensor
Title: Re: tbi troubles
Post by: J.C. on April 01, 2014, 12:16:24 AM
Wiggled and unplugged, and plugged back in. If I unplug map sensor it will stall, would it still do that if it was bad? Had a buddy say to check fuel pressure, he said it can make it run funny.

The 88 has a clogged egr, when I rev it up under the hood, I get smoke from somewhere,  not sure where tho. I took the vac line off and the hole is plugged with carbon. I plugged the line at the manifold, will that be enough? 88 runs great till I get down the road, then ses light comes on. I can push clutch in, turn off,back on and it runs great for another 20 seconds then light comes on and runs like crap.
Title: Re: tbi troubles
Post by: burl on April 01, 2014, 01:00:34 AM
Could be a headgasket ready to pop... do compression test and make sure they dont leak down
Title: Re: tbi troubles
Post by: J.C. on April 01, 2014, 01:02:39 AM
I'll check it when buddy brings over tester
Title: Re: tbi troubles
Post by: xjs3667 on April 01, 2014, 01:04:41 AM
It sounds like one of three things, map sensor, tps, or coolant temp sensor,  these three control the timing and the fuel/ air ratio, any one of them go out and it won't throw a code, but it will run like crap, if at all,  unplug all 3 sensors, it will put it limp mode and see if runs better or still runs like crap, but it sounds like one of them sensors is bad and its making it run like crap which is making it throw the knock sensor code, also if the knock sensor is bad, it will override those three sensors and try to adjust the timing.
Title: Re: tbi troubles
Post by: xjs3667 on April 01, 2014, 01:05:49 AM
I have a scanner I could hook up and look at all the live data, and pinpoint it if need be...
Title: Re: tbi troubles
Post by: J.C. on April 01, 2014, 01:09:51 AM
Temp sensor is new on 88, haven't replaced it on 91 yet. Tps on 91 is new tho. A scanner would be sweet, solve alot of problems without too much of a headache. I'd throw you a few bucks for your time
Title: Re: tbi troubles
Post by: 95-Jeep on April 01, 2014, 03:46:42 AM
Ignition module can cause that as well
Title: Re: tbi troubles
Post by: burl on April 01, 2014, 04:01:10 AM
Ive got a scanner too
Title: Re: tbi troubles
Post by: lilred on April 01, 2014, 08:54:54 AM
Triple checked your firing order? Lol just trying to point out the obvious since you said it ran fine before the swap
Title: Re: tbi troubles
Post by: J.C. on April 01, 2014, 11:57:19 AM
Has a new distributor and ign module in 91, 88 has newer one that's about 8 months old. Xjs is about 4 miles away, thanks tho. I checked firing order a few times. Not sure why it ran better before....
Title: Re: tbi troubles
Post by: J.C. on April 02, 2014, 11:12:11 PM
Thanks Kevin (xjs3667) for stopping by today. 88 is running better now, haven't made it up to get that O2 Sensor yet. I'm going to try to get it tonight and put it in tomorrow. Still have to get gas for the 91. Thanks again!
Title: Re: tbi troubles
Post by: xjs3667 on April 03, 2014, 01:06:54 AM
Not a problem, I'll be around when ya you get some gas for the other truck loll just get a hold me :-)