So I am doing some more testing today and I think I'm narrowing down the problem just not sure what the issue is. I unhooked the O2 sensor to keep it in open loop to see if there was a difference. There was not. But I was still seeing O2 sensor voltage? WTF is that normal? Hooked it back up and did a base idle reset and just wanted to see what the computer thought when I played with the idle speed with the IAC unhooked. If I set it high it lowered the counts but never got below 13. If I set it low the counts would climb until I set it back under 750 and the counts would stop but not lower. This got me thinking. So I set the base idle to 700 with the IAC unhooked as per service manual. Left the IAC unhooked and put the truck in gear. Idle dropped to 500 and stayed there. it also stayed in open loop. Now I was watching the ecu trying to raise the IAC counts all the way up to 145. The O2 was reading 695. but BLM was still at 128 because it was in OPEN loop still. I reved the engine with the brake on up to 750rpm. It went into CLOSED loop and my BLM dropped to 115. This I believe means the engine is running RICH. Correct me if I'm wrong. And the IAC is trying to compensate for it. I also noticed that when I went back to park it idled at 700-750 no problem but it went back to OPEN loop.
So here is my thoughts on this. When I bought this truck it had been sitting for awhile only being moved around the lot it was at. It ran good but was sluggish. On my way home it ran out of gas. Gauge was froze at 1/4 from sitting unmoved for so long. When I filled it up I ran some fuel system cleaner thru it. It ran like **** after about 20 miles. I changed the fuel filter and it was full of crap. Figure the fuel system cleaner loosened up a bunch of stuff in tank and lines. so I ran that tank down and changed the filter again and It was better but it still ran kind of ruff. I figured it got into the injectors. Their spray pattern was a bit irregular. So I did a rebuild kit on the tbi with new injector screens and they indeed had garbage in them. cleaned them and when I put them back in they had a nice even cone of spray. and the truck ran smooth. Problem solved. RIGHT? Well what if they are dumping to much fuel? although it runs good and runs great at WOT. I may have the base Idle set way wrong because they are dumping fuel. This would explain why my IAC counts in gear at 750rpm are at full open 145 counts. I don't have anyone to help at the moment but I have never had someone sit in the truck with it in gear while I watched the injectors to see if they may be leaking or dripping or I don't know what. Could it be as simple as Needing New Injectors? Wouldn't that be something. Just hashing this out while I type. If you have an opinion on this please speak up.
Thanx
So here is my thoughts on this. When I bought this truck it had been sitting for awhile only being moved around the lot it was at. It ran good but was sluggish. On my way home it ran out of gas. Gauge was froze at 1/4 from sitting unmoved for so long. When I filled it up I ran some fuel system cleaner thru it. It ran like **** after about 20 miles. I changed the fuel filter and it was full of crap. Figure the fuel system cleaner loosened up a bunch of stuff in tank and lines. so I ran that tank down and changed the filter again and It was better but it still ran kind of ruff. I figured it got into the injectors. Their spray pattern was a bit irregular. So I did a rebuild kit on the tbi with new injector screens and they indeed had garbage in them. cleaned them and when I put them back in they had a nice even cone of spray. and the truck ran smooth. Problem solved. RIGHT? Well what if they are dumping to much fuel? although it runs good and runs great at WOT. I may have the base Idle set way wrong because they are dumping fuel. This would explain why my IAC counts in gear at 750rpm are at full open 145 counts. I don't have anyone to help at the moment but I have never had someone sit in the truck with it in gear while I watched the injectors to see if they may be leaking or dripping or I don't know what. Could it be as simple as Needing New Injectors? Wouldn't that be something. Just hashing this out while I type. If you have an opinion on this please speak up.
Thanx