Engine Hesitation . . . Can Anyone Diagnose?

[bdonkersgoed]

Hello everyone,

I have beenhaving a problem with my 1992 ES300 (manual transmission) for the past month.

Quite often, when I try to accelerate hard, the engine hesitates realy badly. This is especially frequent when I am lower on fuel (1/4 tank or below) but it has happende around the 1/2 tank. What happens is, I can be in first or second gear and I punch the accelator a little . . . the car starts to take off, then the engine hesitates for a second (as if it is starving fuel) and then kicks in again. When it kicks in, the tach jump about 500 rpm, and the car leaps forward. It feels and looks like I am someone who doesn't know how to drie stick, and it is embarassing.

When my car is near empty, it is terrible. Then I can't even take off from a stop light accelerating super slow without this happening. The car is almost undrivable when the fuel is this low. When I take off from stop lights, the jolt is so bad that is squaks my tires.

I think I have describde this as accurately as I can. Does anyone have any suggestions?

Thanks!

Bryan

[jragosta]

Just a guess, but it sounds like a plugged fuel filter.

There are a number of other possible options (fuel pump could be failing, for example), but I'd bet that it's the filter. Fortunately, that's cheap to fix.

Another thing to consider is debris in your gas tank. I'm not sure how you'd go about checking that or fixing it if it's the problem. Maybe there's a drain plug you can look for?

On some cars, there's a screen on the fuel pump inlet. It's also possible that this is getting plugged up. I suspect you have to drain the tank and pull the fuel pump to check that.

I'd go with the filter first and then start looking for debris in the tank or fuel pump screen.

If that doesn't fix it, you're probably stuck with some more detailed (and expensive) diagnostics.

[bdonkersgoed]

Thanks . . . that seems to make sense. I'm going to try replacing the fuel filter first as you suggested. How often is the fuel filter supposed to be replced?

Also, is it easy to replace the fuel filter? Is it something I can do myself? Where is ti located?

Thanks!

Bryan

[dropspace]

the fuel filter is under the hood on the driver side near the wheel well. metal fuel line goes out the bottom down to the fuel rail and the top has a flexible tube leading to the fuel intake.

you need to put a wrench on the bottom nut before you take it off or you run the risk of rupturing the fuel line.

there is a silt filter in the tank on the 92 es so the fuel filter doen't have to filter much. but its an easy fix so you might as well try it and see if it helps.

[bdonkersgoed]

What is a silt filter? Is that like a kind of prefilter? Can it get clogged up?

Thanks for the help!

Bryan

[amf1932]

The silt filter is at the bottom of the fuel line in the bottom of the fuel tank. It's a wire type of mesh. It filters out larger impurities before it gets to the final filter under the hood.

[SKperformance]

Check the intake for rips in it

you may have multiple problems

I would also check your fuel pressure also. You may have bad vsv's

[bdonkersgoed]

Well, I am taking my car in to the shop on Saturday, so I'll see what happens. I told them to do a tuneup, check out my suspension issues, and replace the fuel filter and spark plugs (and I made sure they knew only to replace with original Densos). Hopefully the problem goes away . . .

Regards,

Bryan

[Lexusfreak]

Where do you take your car for service Bryan? & dealer or independent shop? & where abouts?

[bdonkersgoed]

I take my car to an independent mechanic . . . they are pretty cheap, and only fix what needs to be fixed (unless I specify otherwise). I really like that attitude because I hate it when mechanics want to replace an entier assembly when only one component is broken . . .

The mechanic that I go to does no have an extravagent looking shop, btu they do good work and are super friendly. It's called Byma's Tire and Auto on Bridgeport Street in Waterloo, ON.

I once had a flat tire in my Bridgestone Blizzak (due to a nail) that I didn't buy from them. They were the closest garage, so I took it to them. They changed my tire (which was under a road hazard warraty that I didn't know I had!) balanced the tire, installed it and everything and sent my damaged tire back to Bridgestone and didn't ask for a dime! I had never been a customer before, but they won my loyalty right then and there :D

As an update, my car still seems to do this hesitation. I never got the fuel filter changed though, because they said it was so badly rusted there that there were scared to change it in fear of wrecking the fuel line (which they suggested will need replacing very soon :( )

Regards,

Bryan

[bdonkersgoed]

Sorry, but I am not very good with mechanics . . . where is the aur intake, and how do I check it?

Thanks!

Bryan

[jragosta]

As an update, my car still seems to do this hesitation. I never got the fuel filter changed though, because they said it was so badly rusted there that there were scared to change it in fear of wrecking the fuel line (which they suggested will need replacing very soon :( )

Based on what you have done, you still have 2 things to look at:

1. The fuel intake screen.

2. The fuel filter.

Given that you're getting heavy rusting in your fuel line, I'd suggest having both done - as well as replacing the fuel line. It won't be cheap, but it's certainly less expensive than having the fuel line develop a leak and pouring gasoline on a hot intake manifold.

[SKperformance]

good thought about the rusty fuel lines JR

The filter is probably clogged which rarly ever happens for any other lexus as they are so big

[jragosta]

good thought about the rusty fuel lines JR

The filter is probably clogged which rarly ever happens for any other lexus as they are so big

One more thing. Buy gasoline from reputable companies. A rusty gas line either means that he lives in a very salty area or is buying cheap gasoline with lots of water. That's probably why the fuel filter (or fuel strainer) got clogged - rust particles.

[SKperformance]

good thought also jr

but hsi whole car on the outside is rusty so it is outside in not from the fuel lines itself

[SKperformance]

I also jsut mentioned to a member with a 93 to change his rotor and cap as they all go bad eventually and crack which under certain speed can move into and out of place due to centrifical force.

a cheap upgrade for power and gas milage

[bdonkersgoed]

I already had the cap and rotor and plugs replaced . . . that is when the hesitation started :P

Well, with regards to my gas, I only use Shell fuel, which I believe is supposed to be one of the better fuels. The rusty gas line is due to all of the friggen salt here in Canada :( Kind of unavoidable :( I should have had my car undercoated, and am now feeling the pain :(

I am taking my car to a Lexus dealership today to see what they have to say. Hopefully it is minor.

Thanks,

Bryan

[SKperformance]

If it started after the cap change i would say it is either a cheap aftermarket one or the wires may have been pulled and are not makign proper contact anymore.

btw shell has the worst gas around, i used it for years and now would rather run out than use tehm as i lost power and milage using their crap with all 3 of my cars

[bdonkersgoed]

I always thought that Shell was supposed to be pretty good? I have been using Shell in my cars for the last 5 years (mainly because I get Airmiles through Shell :P)

But, I also liek the fact that Shell is a Dutch company and I am supporting my fellow Dutchmen :P Not that it really matters :P

Regards,

Bryan

[bdonkersgoed]

By the way, my ES300 is making it's first trip to the Lexus dealership today to have the rough idle checked out, so hopefully it should be running smooth again today B)

Regards,

Bryan

[jeptik]

i have been reading your postings with interest, since I am having a similar problem....I am experiencing a loss of power on acceleration...changed the plugs, rotor, cap, ignition wires, fuel filter and also flushed the injectors...the problem still persists. My mechanic now suggests that it might be one or more of the fuel injector that might be bad. I also have a 1992 ES300...automatic.

Would really like to know the outcome of your trip to the dealer......

[SpeedRacer959]

If the problem started after you had some specific work done, then I think you may have found your problem.

[jeptik]

Actually the problem started before I had the work done....it improved slightly after, but still having the loss of power.

P.S. I have always used Super unleaded (Octane 94 - Sunoco) in my car....

Bryan, what's the verdict from the dealer????

[bdonkersgoed]

Hey man,

Check out my last couple of posts in this thread:

Other Thread (Dealer Outcome)

Sounds like I may need a nwe car :(

Anyways, the rough idle and exhaust fumes were due to a vaccuum hose or something. Not really sure, but they fixed it and it wasn't too big of a deal. The idle isn't perfect yet, but that is because the independent mechanic put in A/C Delco plugs instead of the orignal Densos like I told him 5 times!!

Oh well, hope this helps,

Bryan

[jeptik]

Well I took the car to the dealer and after spending over $300 they were able to tell me that 2 of the injectors "might" be bad. Can you believe that, they can't diagnose the exact problem after hooking it up to the machines...at CDN$107 per hour I decided not to have it fixed at the dealer...so I am taking it to my mechanic, CDN$50 per hour to have the injectors replaced. I am keeping my fingers crossed and hoping that would fix the problem :(