91 LS engine sputtering, no power problem
07-23-10, 04:01 PM
#16
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Dan, any chance you are in SoCal? I'll bring you frothy beverages (in sets of 6) and lend a hand (albeit unskilled) to watch.
I spoke to two mechanics, and one said they'd try to troubleshoot it for $95 and need to hang on to the car a few days. The other was a straight-shooter and basically said it's a waste of his time and my money if the problem can't be duplicated.
I spoke to two mechanics, and one said they'd try to troubleshoot it for $95 and need to hang on to the car a few days. The other was a straight-shooter and basically said it's a waste of his time and my money if the problem can't be duplicated.
07-23-10, 04:03 PM
#17
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JRitt, have you changed the rubber o-ring on the gas cap? Supposedly, it has a thin channel that lets air pressure out, but as it gets old, stops doing what it's supposed to. This info was from my former mechanic (who spent several years at lexus) as well.
Thanks for the responses guys. I scoured this board after the very first time it happened, but came to the same conclusion that there was no definitive answer. I was hoping that by now someone had sorted it out. Apparently, not completely!
I tried to take note as closely as possible of the condition parameters on the heat and fuel situation. I'm just glad I'm not crazy!
The one thing I am continually surprised by is the amount of pressure in the gas tank every time I open it for a refill. I've never seen another car quite like it. It practically blows the lid off when you get down to the last two threads while unscrewing!
In the name of science, I guess I'll just hold off on the fuel filter swap, and try to keep my gas tank above half for the rest of the summer. I'll report back.
I tried to take note as closely as possible of the condition parameters on the heat and fuel situation. I'm just glad I'm not crazy!
The one thing I am continually surprised by is the amount of pressure in the gas tank every time I open it for a refill. I've never seen another car quite like it. It practically blows the lid off when you get down to the last two threads while unscrewing!
In the name of science, I guess I'll just hold off on the fuel filter swap, and try to keep my gas tank above half for the rest of the summer. I'll report back.
07-23-10, 04:06 PM
#18
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yeah im in so-cal. im not sure when im going to be able to do it though...kinda busy, and trying to figure out when i can. Im trying to coordinate doing it for when i can use my friends lift. I'll try and let you know when i do
07-23-10, 04:07 PM
#19
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BrunoMagli, I saw my CEL flash a few times in succession when the engine was sputtering at its lowest rpms when it was about to stall, but haven't gotten around to paper clipping the OBD. Is that the proper way to make a jumper setting/cable? Also read somewhere that I should yank the negative battery cable to reset the computer, but maybe I should get the codes prior to doing that. And get codes afterwards if there are any...
I am having the same problem....When I bought my LS400, a 1993, it had been sitting for 3 years. It had very old gasoline in the tank. The old fuel pump was rusted and locked up. The fuel pump was changed but not the filter. Car ran fine once the old gasoline was sucked out of the tank and replaced with new fuel, pump and filter. I changed the filter again last week and it was full of rusty dirty looking gasoline on the intake side of the inline filter. I suspect the Strainer in the tank is partially gummed with residual Varnishy gasoline from the bottom of the tank. I have run a can of seafoam thru it about 4 months ago.
Have been driving the car since December of 09. This is the 1st summer I have had with this car and its not pretty. The engine will heat up at traffic light with the AC on. I can turn the AC off and the guage drops down to normal in less than a minute.. While in motion with the AC on not a single problem. The AC will chill a can of beer on the highway and engine temp needle stays 1 hair above the mid way point. This past winter I changed the thermostat because the engine wasn't getting hot enough...Imagine that...
I wanted to drive this car and learn it. So since it has run fine since I have put it on the road, I want to start changing things 1 at a time to see what fixes what. That IMO, is the only way to NAIL this problem and Post back so that everyone knows what to do. I have the same symptoms that Land people to this post.....
HOT DAY- Power loss, engine sputtering, skipping like its running on 1 bank of cylinders....
I can see that changing the plugs and Caps based on reading makes the car run better, but doesn't fix the problem in MOST...Not all, but most cases.
I would think a misfiring engine would generate a CEL (Check Engine Light) from the Knock sensor...such is not the case as I haven't heard anyone mention this....
Sounds to me like Low fuel pressure for whatever reason. Here's my take on this:
-My LS runs Worst the lower the Fuel level, like less than 1/4 but not Low fuel light on yet...Like it's starving for fuel...The Same way it does....WHEN IT'S HOT! So...either the ECU is not allowing the fuel pump ECU in the trunk to run at full speed when its Hot to keep up with Engine demand for more fuel, (90-92 1st gens don't have FP ECU's) Or, with Low fuel in the tank the pump heats up, or there may be some Cavitation somewhere on the delivery of fuel thru the line with low fuel..hell I don't know....
-I can put in 20 bucks of 87oct and it runs great, Much better...lots of power! So there goes the "Ignition" theory...
In my case at least..
My plan.....instead of Easter Egging a whole bunch of ***** all at the same time, I am going to change things 1 at a time to see what fixes this problem.
I am starting with my FREE NGK-R Plats I just got from Autozone...(Reward card redemption).
I'll post back later this weekend. Oh..I have no problems at all at night, with the ac off. Car runs great mostly all the time at night when its cooler like 80 degrees and below on the dash cluster....but still gets a little sluggish when the level get down to 1/8 tank... I miss the old 280ZX with the little gauge under the fuel needle that went from 1/8>>> 1/16 >>>> 1/32 of a tank of fuel down to 0/0...Thats just d@mn insane to have that kind of information knowing you got 100 miles to next gas station!!! Lol!
I holla back later kats..
Have been driving the car since December of 09. This is the 1st summer I have had with this car and its not pretty. The engine will heat up at traffic light with the AC on. I can turn the AC off and the guage drops down to normal in less than a minute.. While in motion with the AC on not a single problem. The AC will chill a can of beer on the highway and engine temp needle stays 1 hair above the mid way point. This past winter I changed the thermostat because the engine wasn't getting hot enough...Imagine that...
I wanted to drive this car and learn it. So since it has run fine since I have put it on the road, I want to start changing things 1 at a time to see what fixes what. That IMO, is the only way to NAIL this problem and Post back so that everyone knows what to do. I have the same symptoms that Land people to this post.....
HOT DAY- Power loss, engine sputtering, skipping like its running on 1 bank of cylinders....
I can see that changing the plugs and Caps based on reading makes the car run better, but doesn't fix the problem in MOST...Not all, but most cases.
I would think a misfiring engine would generate a CEL (Check Engine Light) from the Knock sensor...such is not the case as I haven't heard anyone mention this....
Sounds to me like Low fuel pressure for whatever reason. Here's my take on this:
-My LS runs Worst the lower the Fuel level, like less than 1/4 but not Low fuel light on yet...Like it's starving for fuel...The Same way it does....WHEN IT'S HOT! So...either the ECU is not allowing the fuel pump ECU in the trunk to run at full speed when its Hot to keep up with Engine demand for more fuel, (90-92 1st gens don't have FP ECU's) Or, with Low fuel in the tank the pump heats up, or there may be some Cavitation somewhere on the delivery of fuel thru the line with low fuel..hell I don't know....
-I can put in 20 bucks of 87oct and it runs great, Much better...lots of power! So there goes the "Ignition" theory...
In my case at least..
My plan.....instead of Easter Egging a whole bunch of ***** all at the same time, I am going to change things 1 at a time to see what fixes this problem.
I am starting with my FREE NGK-R Plats I just got from Autozone...(Reward card redemption).
I'll post back later this weekend. Oh..I have no problems at all at night, with the ac off. Car runs great mostly all the time at night when its cooler like 80 degrees and below on the dash cluster....but still gets a little sluggish when the level get down to 1/8 tank... I miss the old 280ZX with the little gauge under the fuel needle that went from 1/8>>> 1/16 >>>> 1/32 of a tank of fuel down to 0/0...Thats just d@mn insane to have that kind of information knowing you got 100 miles to next gas station!!! Lol!
I holla back later kats..
07-23-10, 04:29 PM
#20
Definitely try to read the codes before you clear the memory. The paperclip trick should work.
I had a coil go bad and it was difficult to detect. I've always had difficulty bench testing coils because one of the resistance measurements (I believe it's the secondary) is on the order of ohms so it's very sensitive to how you connect the test leads to the coil.
Symptoms of mine were a misfire/hiccup at idle with a warm engine (ran fine when cold). It ran fine under heavy acceleration. There were no CELs.
My wife's 2000 Honda Civic had bad spark plug wires, on this the car ran fine when cold, idled fine when warm, but would "bog" when the throttle was floored. It did it when driving (ie pulling away from a light with the gas floored) and also in the garage, hood propped, warm engine, with your hand snap the throttle valve open and it bogged.
A quick test of the fuel pump - unscrew the gas cap and hold your ear to it, let a buddy put the key in ignition, turn to the "on" position (don't start the car), and you should hear the pump whirr for a couple seconds. Try this several times and make sure that it's loading up.
I pulled a coil from a wrecker and subbed it into my car and it's been running fine since. Ironically, I had just replaced the coil so this brand new coil was defective.
Hope that helps.
I had a coil go bad and it was difficult to detect. I've always had difficulty bench testing coils because one of the resistance measurements (I believe it's the secondary) is on the order of ohms so it's very sensitive to how you connect the test leads to the coil.
Symptoms of mine were a misfire/hiccup at idle with a warm engine (ran fine when cold). It ran fine under heavy acceleration. There were no CELs.
My wife's 2000 Honda Civic had bad spark plug wires, on this the car ran fine when cold, idled fine when warm, but would "bog" when the throttle was floored. It did it when driving (ie pulling away from a light with the gas floored) and also in the garage, hood propped, warm engine, with your hand snap the throttle valve open and it bogged.
A quick test of the fuel pump - unscrew the gas cap and hold your ear to it, let a buddy put the key in ignition, turn to the "on" position (don't start the car), and you should hear the pump whirr for a couple seconds. Try this several times and make sure that it's loading up.
I pulled a coil from a wrecker and subbed it into my car and it's been running fine since. Ironically, I had just replaced the coil so this brand new coil was defective.
Hope that helps.
07-24-10, 08:47 AM
#22
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....Bit of an Update. Since it's very hot here during the day, my shop is like a Microwave oven so i did this last night. I don't remember if I mentioned this or not but I had been having this issue we are talking about now, as well as the engine temp creeping up, with the AC on, at a traffic light. What I found was the left fan was pushing air thru the condenser, and the right fan was Pulling! What?...yep..my mistake. I am using "92 model fans and the connector plugs are different from a "93. So I made jumpers and had the polarity wrong on one side. So basically I had a fan Fighting the System. Maybe now since both electric fans are Pushing air this problem will not reoccur.
Now for the MEAT of this topic. I changed the following last night:
Both Dist Caps / Rotor buttons
Spark Plugs......
Test Drive resulted in a phenomenal change in performance...Big change. Runs smoother, has more power. Initial hard acceleration when pedal was floored, ECT-Pwr mode was Great acceleration with No sputtering, no jerking, a little more than 1/4 in the tank. So I went out and cruised around with all the little cereal box cars and obnoxious sounding stove pipe Honda's for about an hour. On the way home about 2 miles from home I floored it again....Sputtering...Jerky.... Fuel Level 1/4... So in My opinion, this is a fuel related issue with possibly IN MY CASE being the in-tank strainer on the pump may be partially clogged since the car sat for 3 years and Old gasoline has been run thru the system even after the new pump was put in. SEAFOAM today Chaps!!!!
I'll check back in time permitting with an Update.
~BM
Now for the MEAT of this topic. I changed the following last night:
Both Dist Caps / Rotor buttons
Spark Plugs......
Test Drive resulted in a phenomenal change in performance...Big change. Runs smoother, has more power. Initial hard acceleration when pedal was floored, ECT-Pwr mode was Great acceleration with No sputtering, no jerking, a little more than 1/4 in the tank. So I went out and cruised around with all the little cereal box cars and obnoxious sounding stove pipe Honda's for about an hour. On the way home about 2 miles from home I floored it again....Sputtering...Jerky.... Fuel Level 1/4... So in My opinion, this is a fuel related issue with possibly IN MY CASE being the in-tank strainer on the pump may be partially clogged since the car sat for 3 years and Old gasoline has been run thru the system even after the new pump was put in. SEAFOAM today Chaps!!!!
I'll check back in time permitting with an Update.
~BM
07-24-10, 08:53 PM
#23
Bad gas.
There is more Alcohol in gas than what is told to the public, and it is very hygroscopic, it attracts water. I think this has alot to do with some bad running engines in cars nowdays.
There is more Alcohol in gas than what is told to the public, and it is very hygroscopic, it attracts water. I think this has alot to do with some bad running engines in cars nowdays.
08-02-10, 04:10 PM
#24
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Thread Starter
2 weeks, 147 miles, sputtered again
As the title explains, in the past two weeks, I've only put on 147 miles on the car, with a can of Seafoam in the tank. It was hot yesterday, had the a/c on and the fuel gauge was showing just over half. Parked on an fairly steep incline, went inside to a friend's house and hung out for 90 minutes.
When I got back into the car and started it, sounded like some faint noises were coming from behind the back seats. Drove down the street and onto a main road and then the sputtering issue happened again for a few minutes. I turned off the a/c (still not sure if it's related), and gave it some gas to keep the revs up. Pulled into a gas station immediately after rolling down the hill and topped the tank off (9.5 gallons). That works out to about 15.5 miles per gallon, pretty weak given about 1/3rd of the 147 miles were shorter freeway trips.
It seems as long as the car is moving or my foot is on the gas, it won't sputter, so I took the toll road and the freeway home without problems. Gonna dump the two bottles of Valvoline Complete Fuel System treatment I have sitting around the garage into the tank.
When I got back into the car and started it, sounded like some faint noises were coming from behind the back seats. Drove down the street and onto a main road and then the sputtering issue happened again for a few minutes. I turned off the a/c (still not sure if it's related), and gave it some gas to keep the revs up. Pulled into a gas station immediately after rolling down the hill and topped the tank off (9.5 gallons). That works out to about 15.5 miles per gallon, pretty weak given about 1/3rd of the 147 miles were shorter freeway trips.
It seems as long as the car is moving or my foot is on the gas, it won't sputter, so I took the toll road and the freeway home without problems. Gonna dump the two bottles of Valvoline Complete Fuel System treatment I have sitting around the garage into the tank.
08-02-10, 05:24 PM
#25
I had the same problem and finally replaced the MAF sensor I cleaned it 2 -3 times it worked for a while then it just starting spurting I went to a junk yard and got a used one for $135.00 and no more problems I got mine at junk yard called 999 in Santa Ana Ca 714-569-1999 ALL HE HAS IS USED LEXUS PARTS it's been 3 months and no problems
good luck
good luck
08-03-10, 01:56 PM
#26
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JRitt, have you changed the rubber o-ring on the gas cap? Supposedly, it has a thin channel that lets air pressure out, but as it gets old, stops doing what it's supposed to. This info was from my former mechanic (who spent several years at lexus) as well.
On my car, the problem is not AC related. My air conditioner stopped working last Fall, and I have experienced the problem since then on multiple occasions. Also, the very first time the problem occurred was when my AC was working and turned on. Therefore my conclusion is that it is not related to the AC system.
I also tried turning my heater on full blast the last time I ran into the stuttering issues. It didn't seem to make any difference at all.
Finally, I looked back through my car's maintenance records, and there are a couple of instances of the previous owner running seafoam through the car. My guess is that was an attempt to cure this issue, or a preventative step to keep it from happening again. Therefore, I don't think that is a viable long-term fix for this problem. It will reoccur.
BrunoMolly,
Thanks for all of the feedback! Like you say, "fuel-starved" is precisely the best way to describe how the car feels and behaves when the problem occurs. My car has been driven consistently from day 1 by the previous two owners, without any substantial time being parked. I have ruled out bad gas in my case, and I doubt anything in the fuel system is clogged, etc. with almost daily driven use.
I've also have never had any CEL's or other codes pop up on my car, so no indications of misfires, knock, etc.
I'm going to leave my car alone for now and keep playing with the fuel level. I haven't driven it much lately, but I'll try to put some more miles on it. The weather is supposed to remain hot and humid where I am, so plenty of opportunity to get some heat into it.
If I can get the problem to arise with more than 1/2 tank of fuel on board, then I'll take a look at the MAF next.
Thanks again guys.
08-04-10, 12:28 AM
#27
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another possibility...
Not sure how I missed this thread during the course of my researching the forums for issues similar to what I'm experiencing: https://www.clublexus.com/forums/mai...em-solved.html
Does anyone have a diagram of where this part goes (fuel pump resistor, 23285-50010)? There used to be really useful, exploded diagram/drawings posted on toyo diy, but I guess Toyota forced them to pull them off the site. Lame
Does anyone have a diagram of where this part goes (fuel pump resistor, 23285-50010)? There used to be really useful, exploded diagram/drawings posted on toyo diy, but I guess Toyota forced them to pull them off the site. Lame
08-04-10, 07:51 PM
#28
Lexus Test Driver
The resistor is located on the front portion of the passenger side wheel well in the engine compartment. Below the box that houses the fuel relay. In the area of the intake / air filter. Its easy to access / replace. Attached is a picture of an old resistor for a 1st Gen LS...
08-05-10, 08:35 AM
#29
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hey guys i have a 92 and i may have had a similar problem, i chalked it up to bad gas, but before i could rule that out my water pump started leaking so i dug in and was replacing it and when i was pulling off my left side distributor cap and cam sensor i noticed an open in the shielded wiring going to the cam sensor, so i obviously repaired it and finished the water pump/timing belt and no issue, so was it bad gas or an intermittent short from that sides cam sensor causing the ignition to fire crazy....... i guess ill never know but something to chew on for you guys
08-06-10, 12:00 PM
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My '92 has done this several times. Gas level doesn't seem to matter. What I did notice is that when it happens the gas pedal seems to "float" and not have any resistance on it until it stops doing it. Like 80% of the pedal travel was not engaged, then it would have normal pedal for the last 20% where I'd try and rev it to get it back. Did any of you experience a funny feel in the pedal along with the problem?