1993 Ls400 Running Rough & Gas Tank Removal

[perks2]

Hi,

I just got my, 1993 LS400 (125000 mileage), car back from the mechanic. It had been there for 1 yr. The mechanic said he checked it and couldn't figure it out.

When I drove it in, it would die after about 5 miles at 60mph. It would pop and crack like it was going to blow up. If I would try to start it as soon as it died..

Them I would let it set for about 10 min. I would drive back home, it wouldn't go

over 5 mph on hills. I'd just about give up and(call the hook) them here we would go at 30 mph the rest of the way home.

Stop at a light, I would excelorate but it wouldn't move for about 2mins. them it would

move.

Before this started, I would drive about 10 Min in town, it would make a swishing noise at about 45 mph. for about 2 min. them it would stop.

My husband brought it home on the trailer today. He wants to know how to take the gas tank off?

My daughter ran it out of gas a couple of times, along time ago. He thinks it might of sucked something up the line. Does anyone have any ideas??

I miss my car.

[1990LS400]

Take the car to a real mechanic who can tell if it is a fuel starvation problem or something else. Don't even think of removing the fuel tank at this point.

[perks2]

Thanks, 1990 LS 400

I will relay this info to my husband.

He now tells me he thinks it is the fuel pump. Could that be possible?

He is a John Deere tractor fixer upper. And does some auto repair sometimes. So, he is using his mechanial brain on the problem. But,I think the Lexus having the computerized workings is just not the same.

[1990LS400]

It's possible that the problem could be the fuel pump but don't just throw money at it. Diagnose the problem. Having the service manuals are priceless. There is a diagnostic procedure for just about everything.

[perks2]

Thanks again, I will keep you posted as we continue with the attemps to repair

the problem. Saturday

[perks2]

Well, fuel tank is out. :( I hope it goes back in without a hitch.

[perks2]

Does anyone no anything about a fuel pump resistor? For the 1993 LS400.

What are the symptoms of a faulty one?

[perks2]

New fuel pump installed , but it didn't fix the problem. Checked the coils they are

not the problem.

Checked for a fuel pump resistor, I don't have one in this car. The

plug is next to the air pump, but no resistor.

Car runs fine until you put it in drive to move. Them it falls on its face. :(

[1990LS400]

Has this car ever ran properly? If it has, the "missing" resister isn't the problem - there were several subtle variations of the gen 1 LS400 and it's not unusual to see unused connectors under the hood on some of the variations. I could speculate about a couple of issues that could cause the problem you are having but I won't do that. Where the heck are you located? I'll bet my indie former Lexus dealer mechanic could figure this out in a few minutes.

[landar]

I would have to agree that you need a "real" mechanic on this one. The first thing to check for are codes. If the engine computer is trying to tell you something, you "listen" to it first. Ultimately, you have to separate this issue into fuel or spark and go from there. You can put a fuel gauge on the rail and see if the pressure is within a proper range. You do not mention if you changed the fuel filter. You may even have a manifold leak which is messing with the fuel mixture. If you do not want to throw a bunch of money down a rat hole, you MUST be methodical in your diagnosis.

Let me give you an example. So the engine starts fine and idles. But when you put it into gear it starts to shake, stutter and lose power. Ok. Get a can of starter fluid spray and spritz some of that into the intake snout and see if you get ANY kind of rise out of her. By 'rise', I mean the engine begins to run correctly, even if for only a moment. If so, its fuel related. If no, then time to explore ignition. We can talk more about that in the next episode.

[SRK]

So you changed the fuel pump without actually checking fuel pump pressure beforehand?

Stop throwing parts at it. Find a diagnostician.

I mean you left the car with the first mechanic for one year (!) so you might be able to find a bit more time to actually make contact with someone intelligent.

[perks2]

Dear Guru Member,

I told my husband what you said about checking the fuel pump first. But, it went on deaf ears:(

Yes, the car has run good when it was first rebuilt.

Then the brake shoes needed replaced. The mechanic shop call and said they could replace them and remove the anti locking tarc, he said it would be a $1000.00 repair versus $150.00 I think and it wouldn't hurt the preformance. I said yes. Well, after I got it back, driving for about 15 min., when I would get to about 40mph, there was a bang 2 or 3 times and a shutter. Like something was locking up. Not in the motor. Them it wouldn't do it again for a long time. Never did find out what that was.

I live in Mid-Missouri. It is 60 Miles to the nearest Toyota Dealer.

That is one of my problems.

Thanks,Perks 2

NEXT: Landar

I am going to see if I can get my husband to do the things you mentioned. The men in my family hate the car. It has been not

something they liked. Myself I really love it. But, I just can't do

mechanic work.

Thanks, Perks2

Next: SKR

I would not be apposed to finding someone like that.

Thanks, Perks2

[perks2]

Dear 1990LS400, I am sorry the first part of my last post, was in answer to your post.

I put Guru Member for your name. :(

Thanks Perks2

[perks2]

Update:

Just took the car for a ride. It seems to do fine until, you accelerate fast.

Them it jirks like your riding a bucking horse until you let up on the accelerator. It doesn't back fire but you would think it could. It raises such a ruckus.

Landar, my husband hasn't done the procdure us told me about. If he

won't I will have my son try it.

Thank you for all of your help so far.

Perks2

[perks2]

Well, none of the men in my family want to work on my car. I haven't been able to get it away from the house, because the roughness is still there , when you excelorate.Today I drove it for a few minutes up the road

in front of the house and then let it idle while I got the lawnmower started and

checked it. When I got in to the car to take it back to the driveway it died when

I put it in Drive. When I would try to start it it wouldn't start. But, I let it sit until

I finished the lawn (3 hrs). Car started right up and drove over to its parking spot. Do you think it might be the ECT causing my roughness and the dieing??

[BentBrain]

Does the car have any CEL codes stored??

Could be a myriad of problems from vacuum leak to MAF to TPS to the *BLEEP* trunk harness.

[landar]

Well, none of the men in my family want to work on my car.

I admire your tenacity in trying to fix your Lexus, however, it might be time to trade this foreign luxury car in on a pickem-up truck. I will bet the men will be very willing to work on a Chevy. You tried. No shame in that.

[perks2]

Dear Landar,

I will find out tomorrow what the "Mechanic" checked on the car. He had never

emailed my bill and told me just exactly what he did. :(

I just really like this car. It makes you feel safe when you drive it. It is a smooth

riding car. It is so quiet. Except when it throws it's fits.

Here are some pictures of her.

Thanks, Perks2

PS I did this once and I couldn't find the post after I posted it..

[landar]

Looks nice Perk. And you are right, it is a very 'safe' vehicle. I have never seen a color combination like yours. I can see why you want to get her fixed up right! Maybe you could look for another local mechanic?

[1990LS400]

I have never seen a color combination like yours.

Whoa! No kidding. It's got the bumper covers and side cladding from an LS of a completely different color - maybe a white one! The available color combinations can be viewed at http://www.toyotareference.com

[perks2]

I am glad you agree. When I got her she had been totaled, so I had them

make the bumper silver and the lower panels. Blue is ok but I just wanted a little

extra umph!! I wanted to change the whole car color, but it had blue interior. So, I didn't. Thanks, P