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1990 Lexus LS 400 shifting problems

My neighbor (no computer, which is why I'm posting) has a 1990 Lexus LS 400 with the V-8 engine, Automatic. Back in July she had her transmission rebuilt (after 17 miles or so of highway driving it wouldn't move forward up the off ramp, just revved, left them stranded.) When she got it back she says she felt like it was shifting late, the rpm's were getting too high before it would gear up.

She also says the engine sounds/runs like crap (probably due to known cheap/poor gas use.) Poor performance.

We changed the oil by the book last weekend, no leaks, old oil was clean and free of debris (although unsure of contaminants, we did not have it analyzed.) (Thanks again to those who replied with info on that previously.)

Later that day it stuck in 'Park'. I went over and wrestled with the shift and buttons to get it into Reverse (or any gear) for her so she could get her kid from school. She's driven it minimally since then.

Today she says it was shifting late, idling really low and lugging it as she tried to go 25mph. As she put it in reverse to get out of the parking spot at the school, it died on her.

There's a known power steering fluid leak, which she is staying on top of. All other fluid levels look good.

I'm looking for some guesses as to the issue at hand here. I don't know where the fuel filter is to change it if it's a bad gas/fuel clog issue- help locating and advice on changing it is welcome. I've got Haynes manuals on my own vehicles so I'm sure the steps/safety issues are the same, but location isn't. It's also a 30+ mile drive back to the transmission shop (still warranted, although the shop apparently has a bad rep for backing up their work) but I could follow behind her to make sure she makes it there. The car was purchased used a year or two ago, I'm guessing it was badly abused, but they're trying to take care of it. Thanks in advance.

Reply to
Pookerz
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This is Turtle.

i have a 1990 LS-400 and all i can say is it seems like a vacuum leak. A vacuum leak can cause all that you have said. The part of transmission not shifting right was close to a vacuum leak but when you said runs ruff it said vacuum leak. You can pull a vacuum hose off it and it will not shift at all and run very ruff.

Try looking at the vacuum hose that connects to the air intake down stream of the air filter and the plastic hose connector can start to break or split to let in air.

I know a few Lexus owners and rare there is nothing wrong with the transmissions but vacuum leaks is.

TURTLE

Reply to
TURTLE

You know, now that I think about it, that sounds like a possibility. When we had the hood up and engine running, checking for any oil leaks after the oil change, I noted that it sounded funny to me. It had a bit of a high pitched whine/hiss, and I immediately thought the air filter might be bad (sounded exactly like a vacuum cleaner with something caught in it while it's trying to run.) So we did check that, and it's still nice and paper white, but the whole setup under those wacky plastic covers along the front above the radiator is really loose and the clips are half gone. I had a heck of a time getting the air filter back in place, but I did get it seated properly and clamp it back down. I'll go have another look/listen after the kids are home, and see if I can find any cracks or splits elsewhere.

Reply to
Pookerz

This is Turtle.

Yea those round air filter is a hard one to get off and back on again.

i had a vacuum leak a few years back and it was the vacuum line attaching on the air intake hose leaving the filter and located about 8 inches from the air filter back toward the air intake of the engine. The plastic male hose connector where the hose connects split and cracked to let air in. It split and started leaking again here lately and had to use J.B. Weld to patch the air leak on the plastic hose connector.

if you get a vacuum leak. they will do strange things to say the least.

TURTLE

Reply to
TURTLE

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