TF999 Annoyance - A question

[Nalanthi]

Good morning, all.

Just trying to get some insight on this...
My freshly built TF999 started displaying some odd symptoms recently and I'm trying to place what the problem may be.

Everything runs and kicks fine until the jeep has been at op temp for about 20-30 mins. At this point every time the throttle is depressed sharply at cruise, everything seems to cut out for a second or two, I'll feel a firm kickdown, then it'll all come back in the desired gear.
Manual shifting does not bear the same results.

I want to blame the linkage (Lokar cable), but... I also kind of want to blame the carb.

It's not really hindering drivability but it's annoying as hell.

Anyone experience something the same?

 

[Lumpy Grits]

This doesn't sound like a tranny issue to me.
What is need'd here is more info on the jeep in question.
Please fill put the info in your profile so we can help you out.
If this jeep is carb'd. I wounder if you could have a gas tank vent issue.
When was the last time a full tune up was done? How long has the fuel filter been in use? When was the last time the carb was rebuilt?
LG

 

[Nalanthi]

Edit made. Sorry for the lack of info.

There is no gas tank vent issue and all filters are new.
I *really* want to blame the carb. This Holley 7448 (came from PO - new about a year ago) is 100% trash and only seems to run/not load up when the float is set stupid low. I'm feeding it via electric pump w/ an FPR set to around 4.5PSI.
She's timed, tuned, and was running quite fine for a weeks now.

I wanted to blame the Transmission kickdown, but as you are probably confirming - not a Transmission issue due to manual shifts being good.

I really want to go back and give my MC2100 a chance, but that was giving me other types of problems. Possibly junk even after having been rebuilt.

 

[Lumpy Grits]

Look for vacuum leaks.
LG

 

[Nalanthi]

I'm 99.9% sure there are no vac leaks.
I've checked for them ad-nauseum.

 

[mriplaybass]

What kind of shape is the Transmission modulator in? It sounds as if you may be experiencing improper shifting which could be causing the engine to work harder than it should due to delayed downshifting when acceleration hard. If the modulator is just starting to go bad, it may allow the shift as you described, but will only get progressively get worse as it wears out. Pull the vacuum line on the modulator and check for Transmission fluid. Even if there is no atf in the line, the modulator could still be bad though.

 

[Nalanthi]

Well, gents... it turned out to be a carb issue (AGAIN).
This time I put the MC2100 back on. The last time it was acting up I did not have the elec fuel pump and FPR. This time she's running cherry.
Not to self: Holley 7448 sucks no matter how you try to tune it.

 

[Lumpy Grits]

Glad you found the issue at minimum 'hit' to the wallet.
LG

 

[Nalanthi]

Yeah... very much so.
I was starting to mull over the idea of buying a complete reman MC2100 because I was not trusting this one after it loaded up and left me stranded for a good 30 mins each time until I could get it to re-start and limp home.

No problems to report on it this afternoon while driving around in 101 degree heat for a good 45 mins. It *should* be ok...

 

[Lumpy Grits]

101* is 'Spring' in the desert-

LG