Have you checked the MAP sensor? and the vac line to it? The symtoms you are describing are pointing my brain towards that. You have one from the running truck you can swap over to check it right? It's worth a shot anyways...
CK5
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Round n round I go, where I stop, I dont even know
- Thread starter cabledawg
- Start date
cabledawg
Secret Squirrel
I'm not to familiar with the MAP sensor on these trucks. I have checked all the vac lines, but I may just replace them to rule out any leaks or collapsed lines. Where is the MAP sensor? Besides a part swap, is there anything to check on the sensor to determine proper operation?
The MAP sensor reads engine load via vacuum. It is on the pass side of the intake up on a bracket. There is a single plastic vacuum line off the back of the t-body, follow this line over to the MAP. Check the rubber fittings at each end of the plastic line just in case they might be dry rotted, cracked or broken. Unplug and remove the MAP from the running truck and plug it into the non running truck. You don't have to bolt it up just plug in electrical and vacuum. Try running the truck, if nothing changes then it wasn't the MAP. Put it back into the running truck.
This is the easiest way to check it out.
This is the easiest way to check it out.
cabledawg
Secret Squirrel
So it's the flat black box then? If that's it, then I suspect the vacuum line is causing the problems. That's the line that keeps popping off the TB. And I noticed the last time I messed with it that the one onthe box side was really looses, but connected. It may not be sealing up well.
Anybody know where to get new rubber vacuum fittings/connectors? My lines were replaced with the engine swap three years ago, but I reused the old rubber fittings. I'll see if the parts truck has anything worth using, but I suspect they're in the same shape if not worse.
Anybody know where to get new rubber vacuum fittings/connectors? My lines were replaced with the engine swap three years ago, but I reused the old rubber fittings. I'll see if the parts truck has anything worth using, but I suspect they're in the same shape if not worse.
GsxrMike
1/2 ton status
I think you should rethink your statement because oil is pretty much everywhere and O2 is also pretty much everywhere. An O2 tank is under pressure, that is why when you oil your gauges they can go boom when opened. I'm not touching your other statment but you have to have O2, fuel and ignition to have fire. Fire is just a chemical reaction, so is your boy scout trick, only it is causing ignition of the fuel and O2.
cabledawg
Secret Squirrel
Damn this is pissing me off! Tried checking/swapping the MAP sensor. No dice, same thing as before. The engine starts and runs for about 30 seconds then the SES light comes on. Once it does the engine will idle up to about 1800-2000 rpms then stall out shortly afterwards.
Took it to a shop and they said they fixed it, but it died within a block. Had it brought back and they said they take a look at it, but said my wiring didnt match thier schematics. About the only thing I've "rewired" was the stuff for the alternator so I could run dual alts. Even then, the second is almost entirely on its own circuit, so it shouldnt make difference on anything else. They charged me $160 and I dont think they even put it on a machine.
So I ordered an ALDL cable and had it overnighted. Should've done this awhile ago, but I'm cheap and thought I could do without it. That's what I get for thinking.
Took it to a shop and they said they fixed it, but it died within a block. Had it brought back and they said they take a look at it, but said my wiring didnt match thier schematics. About the only thing I've "rewired" was the stuff for the alternator so I could run dual alts. Even then, the second is almost entirely on its own circuit, so it shouldnt make difference on anything else. They charged me $160 and I dont think they even put it on a machine.
So I ordered an ALDL cable and had it overnighted. Should've done this awhile ago, but I'm cheap and thought I could do without it. That's what I get for thinking.
GsxrMike
1/2 ton status
So I ordered an ALDL cable and had it overnighted. Should've done this awhile ago, but I'm cheap and thought I could do without it. That's what I get for thinking.
I hate it when thinking gets in the way!
When the shop said they fixed it, what is it that they said they did?
cabledawg
Secret Squirrel
They fixed a ground wire and the wires going to the coil kept coming loose. So today I brought them a new coil harness.
I sat in the parking lot tweeking the TB. I finally got it to run without the SES light coming on, but it still doesnt idle smooth. I might just go get another TB and see if any other problems arise before I move next week
The guy said he put it on the machine, but the aftermarket parts weren't being nice to the machine. Is this true, or did he just hose me out of money for nothing?
I sat in the parking lot tweeking the TB. I finally got it to run without the SES light coming on, but it still doesnt idle smooth. I might just go get another TB and see if any other problems arise before I move next week
The guy said he put it on the machine, but the aftermarket parts weren't being nice to the machine. Is this true, or did he just hose me out of money for nothing?
GsxrMike
1/2 ton status
They fixed a ground wire and the wires going to the coil kept coming loose. So today I brought them a new coil harness.
I sat in the parking lot tweeking the TB. I finally got it to run without the SES light coming on, but it still doesnt idle smooth. I might just go get another TB and see if any other problems arise before I move next week
The guy said he put it on the machine, but the aftermarket parts weren't being nice to the machine. Is this true, or did he just hose me out of money for nothing?
I think $160 is high for diagnosis only! If he is relying soley on his computer to tell him what was wrong I would take it somewhere else.
cabledawg
Secret Squirrel
Well part of that $160 is towing, but it was still about $90 for the "diagnostic" that I dont think was done. Plus I dont think they wanted to think outside the box and just said the aftermarket parts were the issue. I cant imagine in todays age of the aftermarket upgrade frenzy, that he's never had a vehicle with no mods whatsoever prior to mine.
The ground wire he installed was on the bracket for the coil. Since the Holley TBI was bigger than stock I couldnt mount the coil in the stock location. So I made a bracket and mounted it on the firewall, right above the dizzy. In the three years I've had this engine in the truck, it's never been an issue. Now this guy tells me that was part of the problem.
Out of curiosity, does anyone know what the voltage range should look like for the TPS? Since that was one of the codes that came up originally, I want to look at that and make sure it is specs. I'm also going to check the exhaust on the O2 sensor side to make sure there isnt a leak in the header flange or the collector. I've had issues with that in the past, but usually catch it quick due to noise.
The ground wire he installed was on the bracket for the coil. Since the Holley TBI was bigger than stock I couldnt mount the coil in the stock location. So I made a bracket and mounted it on the firewall, right above the dizzy. In the three years I've had this engine in the truck, it's never been an issue. Now this guy tells me that was part of the problem.
Out of curiosity, does anyone know what the voltage range should look like for the TPS? Since that was one of the codes that came up originally, I want to look at that and make sure it is specs. I'm also going to check the exhaust on the O2 sensor side to make sure there isnt a leak in the header flange or the collector. I've had issues with that in the past, but usually catch it quick due to noise.
blazin_blazer
1/2 ton status
pure oxygen & oil needs no ignition source...they only have to meet and it will ignite..it is a chemical reaction like you said,..i would go into it more but i don't want to derail the topic here anymore than i already have.
