Temperature sensitive b***h

[j894]

I'm referring to my truck. '01 blazer.

On cold days sometimes it seems to be so ballsy its nuts.
Go to get on it to pass someone & have it smack you into the seat. A couple of times I've gone to pull out normally, made a slight turn ...burned the tires off & almost lost it (but it rarely seems that ballsy), thats with it running just about at operating temp. Maybe it was a fluke..

Obviously its easy to spin tires while making a turn... but on the other hand just a slight temp change will render it nutless, or it will randomly have power & wont when its cold out. It will see so gutless that theres no feeling to it. Takes much effort to drive, barely goes & wouldn't spin the tires if I tried.

Im not talking the engine temp, before its warmed up. But the air temp. Randomly it run super good, then wont. Around the same temperature or cooler later in the same day. It doesn't run "bad", but just doesnt have much to it.

This seems like some kinda of tunning issue. I was just curious what all readings does the PCM take into account to make it run this well? Is it different A/F ratios, fuel trims, timing tables or something? I've tried running a resistor in place of the IAT to see if I could replicate the results with no luck. & I also have a spare MAF that I've tried without any luck. Dont know a whole lot about it though.

Anyone know the computer side of these trucks well, know how to explain this?

[Sparky2263]

Disconnect the MAF, clear the computer (disconnect the battery) and drive it a few days with no MAF. Problem goes away, you found your problem.

[j894]

I'll have to try that.
I ran it without a MAF before, Accidentally 4got to plug it in.. & it seemed worse. But the computer was never reset or anything. Is that because it had already learned everything with the MAF plugged in?

I'll try that tomorrow.

[Mikz86TA]

Not sure if I follow your issue. But my truck was running ok in the 70-75* temps we just had here. Then it came a 2-day cold front and woahhh......It was like way more responsive and had plenty of pull. Then today it was about 80* outside and it felt like it lost some balls. I was disapointed becasue I just got my MSD coil and 8.5s on today. I wasnt expecting much from jst doing them, but I wish it was cooler so I could get a better representation. I have a 180* thermo and it was still at 210* in traffic. I know there is no substitute for cooler denser air, but even with the Dex-cool gone and a lower stat I would expect it to be no more than 200* and run better. I just need electric fans and get rid of the POS thermal fan.

[j894]

forgot to update this thread:
i ran it without the MAF for a few days.

Pulling out from a stop it seemed to respond slow
It seemed to go a little easier once you got going, & with less effort. but didnt go anymore. Also seemed to run a little smoother like while rolling at first at 3000rpm.

[Mikz86TA]

I feel mine is a little sensitive to temp, but its mostly the humidity change. Recently we have had upper 80s and lower 90s. On the days with the same temp but higher humidity, it seems sluggish. Today it was upper 80s and low humidity. And she felt soooo good. I couldnt help not to have a heavy right foot. Prayin for the stoplights...Hehehe

[Sparky2263]

Stock truck tunes SUCK from the factory. Find someone who is good at tunes. I've seen that **** on Rollins dyno soooo many times.