PhLaXuS

OK...as long as I've had the car there's been this one strange problem: If I start the car when it's been sitting overnight and is cold, put it in Drive (700R4) and hit the gas, everything feels normal until I hit ~5000 RPM. Something begins to slip and really kills my power transfer to the wheels. I've seen that if the car is up to operating temperatures, this still does happen, but the slippage is not nearly as pronounced. It's almost not there. Hot or cold, If I go to WOT and then momentarily cut back to 1/2 throttle at 4500RPM, the transmission will shift into the next higher gear, RPMs drop and then I can floor it again.

NOTE: At 5000RPM, the car is not shaking, it just loses power to the wheels. I can even rev past 5000, but with even more slip. It kind of feels like a manual transmission with a misadjusted clutch that's barely grabbing.

The problem has not gotten any better or worse in the 8,000 or so miles I've had the car. I believe the converter & tranny are factory originals from 1991 and the car has ~166,000 miles. When I got the car, the transmission was overfilled by a few pints. Since I've heard horror stories of people draining fluid only to find that now the transmission will not work when refilled, I just let it stay where it was. The guy I got the car from drove it HARD (He was actually gentle while driving it, but did not perform routine maintenance.) and had it overfilled the whole time, so I thought the damage was already done, if any. The transmission fluid id still a nice red and feels like new. You guys think this is the converter?

Floor guy

Sounds like an internal transmission problem.

PhLaXuS

Anyone else?

luke4907

iTrader: (5)

I doubt it's your converter. If it was your converter I think you'd be experiencing slippage problems at your max torque rpm or other lower rpm, not 5000rpm as you have described.

i know I'm gonna get reamed for this one, but it may be possible your TV cable is not properly set. I may be totally wrong, but the way I understand the system is that it increases fluid pressure in the valve body according to what position the throttle is at. So maybe somehow the cable is set incorrectly so that there's not enough pressure to keep it from slipping, yet the low pressure isn't making it shift. Ya I know it sounds like a bit of a stretch, but it's free to try. I think there's a guide in the tech articles here on TGO.

That's my more optimistic opinion. My pessimistic opinion is internal transmission failure. But in that case I suppose it could be as simple as replacing the shift servos or something (also in the tech articles or linked there). I just want to be clear: Does it do the same thing whether it's a 1-2 shift or a 2-3 shift? If not, I'd suspect the servo or clutches for the corresponding gears.

I'd also spend some time reading this

PhLaXuS

I did check on my way in to work this morning and here's what I found:

1.) The 1-2 shift has a very pronounced slippage around 5000 RPM. i.e. I absolutely cannot gain any more speed if I continue to hold the accelerator down while in this state; I do not lose speed, however
2.) The 2-3 shift has a slight slip ~ 5000 RPM -- almost unnoticeable.

This has me wondering...it does occur on the 2-3 shift, but it is much less intense than on the 1-2. I don't know if this is due to RPM or torque now. I'll check out the link and see what I learn. I would be inclined to think that it's not a burning or deteriorating clutch belt because the fluid looks & smells just like new.

The guy I bought the car from is a friend of mine and maybe 2-1/2 years ago he had a slight transmission leak. We got some brand of $3 transmission stop leak additive and it hasn't leaked since. I've had the car since last August 2004. I have no clue what brand of additive it was, but has anyone ever had a strange problem show up from tranny additive?

luke4907

iTrader: (5)

I've never had a problem with additives, in fact, LucasOil stuff gave me a 3rd gear (C3 tranny) back one time after I lost it. You don't have a shift kit, do you? If not, there is no difference between the 2-3 shift and the 1-2 shift as far as torque converter or engine goes, so that tells me it's not anything related to your converter (since converter spins at engine rpm, and the most stress the converter is put under is during maximum torque, which should not be 5000rpm on your car). Since the fluid isn't burnt up it still sounds like the cable isn't set properly to me. Either that or tranny needs a rebuilt. I'm outta ideas, good luck with that

PhLaXuS

Something very interesting just occurred today: My fuel pump died.

A dying fuel pump could explain all the problems I'm currently experiencing:

·Inability to rev past 5000 RPM in 1st.
·Detonation problem which seems to have no electrical cause.
·And, of course, my car sputtering down the road (just started today)

After telling this to someone I know who lives nearby, he stated the obvious that I couldn't see which was that if the transmission/torque converter were slipping, then I'd still be able to rev past 5000. So!...hopefully my new pump will fix all the above problems. Gotta get it in tomorrow because I have a job interview on Monday.

luke4907

iTrader: (5)

Dead fuel pump should be the cause for all those... 1st make sure the fuel pump relay is working (when you turn the ignition into on position there will be a clicking sound from the relay located on driver side mounted on firewall) then make sure to dedicate the whole day to swap the fuel pump because it's no quick job.

More importantly, the cause of the dead fuel pump may be from your 'checking' the slipping condition revving to 5k, which I assume you've been doing quite a bit of. TPI engines (and their respective fuel and air delivery setups) weren't made for much more than 4500rpm in stock trim. If you plan on any upgrades to your car or have already done so, I'd HIGHLY suggest replacing the fuel pump with a walbro 255lph unit. eBayers sell them for a little more than $100. It'll keep fuel in your engine at the highest rpm and if not then it won't be working so hard as if you had a 190lph unit.

PhLaXuS

OH YEAH, BABY!

Replaced the pump & now can rev up to 6000 in 1st (and then shifts on it's own into 2nd) and I have LOTS more power than I did before the swap. Strange...I must have been one of those odd cases where the fuel pump died over a period of time. It's been doing this for about the 9 months and maybe 9500 miles I've had the car.

So...first time swapping out an in-tank pump:

In the driveway with jackstands and a sucky scissors-type jack took about 4 hours by myself and no hackjob to the body.

P.S. Please don't sit in a puddle of gas like I did. Light Yo A$$ On Fi-ya!

copperhead110

A clogged fuel filter can make your transmission is slipping too.

My car did that. Fortunately I took my car to a honest transmission shop. They test drove it with me in the car and told me the transmission is fine. Change the fuel filter.