Hey Guys,

I need your help. Friend has a 4l60e attached to his 4.3 Blazer and it did something really strange.

We were crusing about 20, and I had just got done installing a custom intake on his truck, so I told him to give it some throttle. He wide opens it, and at about 30mph and 2800, the thing stops climbing. And bucks. Almost as if it was hitting a rev limiter. It didn't bounce so to speak, but it stalled at 2800rpm and wouldn't climb any higher, but it bucked a few times as if were trying to climb rpm.

Example. It climbs the rpm hits 2800. And bucks forward. Still stuck @ 2800 is bucks again, but no change in rpm. WTF?

Does anyone have any idea what so ever?

-Tranny fluid is good.
-Stock Stall
-70k miles

How much do 4l60's go for?

Thank you Guys,

Kyle

 

Sounds like an engine problem to me....Just worked on the engine, now a problem.
Sounds like it's running out of gas.
What year is this truck?
Don't go out and get another transmission because you'd be in for a big disappointment when you find out thats not the problem.

 

Check the intake you just put in there!!!!

 

Yeah, I thought that could possibly be the problem. We did numerous runs in neutral and revved up to 5000 and it did so with ease. Another thing that pretty much makes me feel positive it's not the intake is we did some runs right after the intake swap just to get a feel for it and there were no problems.

The problem first occured 30 or so minutes later after driving. All of a sudden, sort of thing.

The only thing changed on the new intake was the piping and a cone filter. MAF & IAC are in, so no changes.

Thanks Guys. I am truly open to your opinions, I just wanted to clear things up with some more details.

2000 Blazer
4.3, 4L60-e

 

Sounds like it's running lean to me. It will rev high with no load on the engine if it's lean.
The symtoms sound a lot like torque management or something related to the vcm. My camaro would do the same thing except at higher rpm. I deleted the TM and fixed the problem.

 

Hmmm, I did remove the MAF screen. Possibly this sent it lean. I might try and pick up a new maf and see where to go from there.

Thanks.

 

Just a little story that might relate to a lean condition you're possibly having.
I built a old carbed 350 for an s-10 a few years ago. It ran strong all the time.
Then I take it to the track, when I launched it felt like the ignition was shutting off, I figured it was from the increased traction. More traction=more load to the engine=lean condition more noticable.
All I did was jet the carb a few sizes richer and it was fine.

I think you did create a lean condition with the maf, if you get it tuned it should run right and stronger.

 

heY!, i figured it out. Bad fitting after the maf. Got the gap all sealed up and it seems to be running fine now. It was closed on the first trip and slowly slipped off. Got it fixed. Thanks for the tips.

I'm waiting on some tuning to become available. pcm4less is workin on somethin for the model yr.

Thanks for your help,

Kyle