Car Stutters and shakes from time to time.
08-15-11, 09:17 PM
#1
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Car Stutters and shakes from time to time.
basically it is not a constant issue it comes and goes but recently it feels to be ocurring more and more often and for longer spurts of time. Anybody know or expiriencing similar issues.
08-15-11, 09:29 PM
#2
Does it seem to be spark or fuel ? If it seems spark related pull out a spark plug and see if there is oil on the insulator/threads my camry had the spark plug tubes leak oil down where they thread into the head and oil got on insulator causing a lower resistance path to ground causing an occasional miss (usually under high rpm heavy throttle)
Last edited by sam12345; 08-15-11 at 09:33 PM.
08-16-11, 09:58 AM
#4
Pole Position
It could be a number of things. Ya need to figure out if it's air/fuel or ignition related. I would test the coils first to see if they're in spec. One of them might be starting to fail. (drivers side is common) When was the last tune up or timing belt? (plugs and wires) Also check your TPS and AFM. My car was jumping and shaking b/c of the AFM and when I unplugged it, it stopped shaking.
08-23-11, 09:58 PM
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Once I hit about 3,000 rpm I start to feel the stutters, but its a random thing its not consistent it dosen't happen everytime like that but with the improvements it not as often although today I felt it happen, you know the mmm mmm mmm back to back
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08-24-11, 10:04 AM
#8
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Not sure how sensitive toyota maf sensors are but it might benefit from a cleaning. Try this stuff out. Ive had good luck with it.
http://www.amazon.com/CRC-05110-Mass.../dp/B000J19XSA
http://www.amazon.com/CRC-05110-Mass.../dp/B000J19XSA
08-24-11, 10:26 AM
#9
Pole Position
Not sure how sensitive toyota maf sensors are but it might benefit from a cleaning. Try this stuff out. Ive had good luck with it.
http://www.amazon.com/CRC-05110-Mass.../dp/B000J19XSA
http://www.amazon.com/CRC-05110-Mass.../dp/B000J19XSA
08-24-11, 11:18 AM
#11
Pole Position
08-25-11, 02:10 AM
#12
Weird, I used some cleaner I found at a computer store, worked perfectly stopping rough/bouncing idle. I still get chugging at low speed, but I know its my driver side coil causing that issue.
Are you sure its not just dead? One of mine died before suddenly without any major warning signs, it just decided to stall my car one day and did not work properly from then on.
Are you sure its not just dead? One of mine died before suddenly without any major warning signs, it just decided to stall my car one day and did not work properly from then on.
08-25-11, 03:04 PM
#13
DO NOT try to clean the AFM sensor on the pre-VVTi 1UZ's!!!
ANY substance getting on the mirror inside it will render the car undrivable!!!
Cleaning the sensor "can" be done but it's rarely necessary at all unless someone's already done something foolish with some sort of aerosol can to it and at that point the car usually runs horribly or won't run at all...
The car's main E.C.U. will nearly always tell you if your AFM is unhappy.
Put a jumper wire in the car's main diagnostic terminals and count the CEL flashes to determine any error codes and if the AFM isn't one of the codes, DON'T TOUCH IT!!!
Take it from a long time MkIII Turbo Supra owner which uses the same exact sensor in most years of the MkIII Turbo Supra as the early LS400's use, although the LS's metal housing that the sensor screws into is much larger. (Sensor's last 2 digits in its' part number being 11, not 10).
When I bought my 1994 LS400 in February it had a bunch of issues including the AFM making the CEL come on at a stop and go back off again after moving for 10-30 seconds. When I checked the diagnostics and found the AFM code I swapped the sensor module itself with my Supra's AFM sensor module (not the whole metal housing) and the AFM code and CEL went away but I saw no real change in idle or drivability of my LS at all.
ANY substance getting on the mirror inside it will render the car undrivable!!!
Cleaning the sensor "can" be done but it's rarely necessary at all unless someone's already done something foolish with some sort of aerosol can to it and at that point the car usually runs horribly or won't run at all...
The car's main E.C.U. will nearly always tell you if your AFM is unhappy.
Put a jumper wire in the car's main diagnostic terminals and count the CEL flashes to determine any error codes and if the AFM isn't one of the codes, DON'T TOUCH IT!!!
Take it from a long time MkIII Turbo Supra owner which uses the same exact sensor in most years of the MkIII Turbo Supra as the early LS400's use, although the LS's metal housing that the sensor screws into is much larger. (Sensor's last 2 digits in its' part number being 11, not 10).
When I bought my 1994 LS400 in February it had a bunch of issues including the AFM making the CEL come on at a stop and go back off again after moving for 10-30 seconds. When I checked the diagnostics and found the AFM code I swapped the sensor module itself with my Supra's AFM sensor module (not the whole metal housing) and the AFM code and CEL went away but I saw no real change in idle or drivability of my LS at all.
08-25-11, 04:55 PM
#14
I'm actually curious about your vibration issue...
My '94 LS400 cruises at like 2,250 at 70mph and like maybe 2,600-ish iirc at 80mph so why/how are you cruising at 3,000 rpm's?
I spend a LOT of time out on the interstate in my LS and even in town (a small city) the speed limit is like 45-60 on most of our local semi-rural roads here.
It always seems like whenever I get agressive, cold or hot, just started or freeway cruising for an hour doesn't matter, after pushing my LS agressively it starts feeling like a mild intermittent stumble for a few seconds and/or a shudder or vibration very similar to a tire slightly out of balance but that's not the case because sometimes it's totally smooth for the whole 50 mile trip at the same speed, and sometimes after I've pushed it a little agressively it even decides to majorly back off the power for several seconds while I've eased into the gas pedal to gradually pass someone and it keeps losing power until I back off the pedal again then and at some point while letting off I feel it jump back to normal and it goes back to running fine again. If I floor it while it's being odd the car usually still down-shifts and goes although sometimes it really pulls hard and other times it just does okay...
Over the past week, in addition to the random wierdness, three times now it has also decided to spin over normal but spin a lot longer and not even cough or sputter on the first attempt instead of being running within a second of turning the key. Then on the second try it would fire right up like nothing was wrong and run as usual so I just ignored it...
Then yesterday it spun and spun, like 10 seconds or more... second try, third try, fourth try, normal crank and spinning over but no attempt to start at all.
I had to be at work asap so I drove the MkIII Turbo Supra instead and finally took a look at the LS today and here's what I found so far...
Before trying to start it again I put the diagnostic jumper in and got a happy flashing CEL with no codes at all. I tried to start it and got lots of normal crank but no start again today like either spark or fuel was lacking...
I left the key on and inserted the jumper into the fuel pump pins, then a second later I heard a click and started hearing the flow of fuel into the fuel rails so that made me think the pump was fine and I assumed it to be a spark problem but decided to try the key again anyway just for the heck of it.
To my suprise he car fired right up in a second like it used to and began to idle for about 7-10 seconds as usual, then suddenly it slowly started losing rpm's like it was running out of gas that kept slowly dropping for 2-3 seconds, then it surged back up to normal idle for about another 15 seconds before slowly dropping rpm's and then surging back up to idle where it finally stayed like there was nothing wrong at all. I tried the gas pedal and it seemed to respond normally.
So I left it idling and opened the trunk and checked the "Fuel Pump Computer" connection with the car still running, wiggled the plug all around in its' socket on the computer which had no effect, banged on that computer with a screwdriver handle, banged on it hard with my hand, etc, etc, and the car kept on idling and didn't skip a beat.
So most likely either there's another relay in the chain (which apparently only the Cali models got?) or my fuel filter's clogged, or my pump's on its way out which I'm thinking is the case.
When I bought this car the used car lot had replaced the power steering pump right before I bought the car.
The week I bought the car with 184,500 miles on the odometer it got a genuine Toyota/Lexus timing belt, water pump, idler/tensioner pulleys, distributor caps/rotors, NGK Iridium spark plugs, thermostat, "Toyota Red" coolant, full tranny flush with the proper Toyota ATF, diff fluid change, full brake fluid flush with Mobil1 Syntec fluid, oil change with Mobil 1 Full Synthetic and Genuine Toyota/Lexus oil filter, serpentine belt replacement, new Lexus/Toyota front brake pads and "Premium" Wagner rotors (rotors were warped really bad when I bought the car), etc, etc, etc...
The valve clearences were also inspected (trying to find a tick but ALL 32 were still in spec and the tick is still a mystery) and new valve cover gaskets and related gasket maintenance parts and pcv valve/hoses/etc were also replaced in the process...
It also ended up needing an alternator last month but I think I drenched it in steering fluid several times so that's not the car's fault and the alternator that came off was a genuine Toyota alternator.
So it's gotten a pretty thorough going through and was totally drivable and reliable but obviously still not quite 100% right and I'm hoping the fuel pump is the culpret for this minor vibration and stumbling wierdness. I'll be suprised if it's not at this point...
NOTE:
There's a whole thread about an LS that won't tach over like 2,700 or 3,000 rpm's trying to find their problem. Some think it's the TPS (Throttle Position Sensor), others have replaced it and still had the problem and ended up with a bad Main ECU, and there are tons of theories with not so many actual solutions posted...
I've basically driven my car with its' minor random intermittent problems 50 miles each way to and from work, with a few minor annoyances and waited for them to become more apparent so that they could be found and fixed. The car has been totally freeway reliable up until yesterday and if I'd had a few more minutes to test things at the moment that it didn't eagerly fire right up I'm sure I could've gotten it started and driven it all the way to work and back as usual.
My '94 LS400 cruises at like 2,250 at 70mph and like maybe 2,600-ish iirc at 80mph so why/how are you cruising at 3,000 rpm's?
I spend a LOT of time out on the interstate in my LS and even in town (a small city) the speed limit is like 45-60 on most of our local semi-rural roads here.
It always seems like whenever I get agressive, cold or hot, just started or freeway cruising for an hour doesn't matter, after pushing my LS agressively it starts feeling like a mild intermittent stumble for a few seconds and/or a shudder or vibration very similar to a tire slightly out of balance but that's not the case because sometimes it's totally smooth for the whole 50 mile trip at the same speed, and sometimes after I've pushed it a little agressively it even decides to majorly back off the power for several seconds while I've eased into the gas pedal to gradually pass someone and it keeps losing power until I back off the pedal again then and at some point while letting off I feel it jump back to normal and it goes back to running fine again. If I floor it while it's being odd the car usually still down-shifts and goes although sometimes it really pulls hard and other times it just does okay...
Over the past week, in addition to the random wierdness, three times now it has also decided to spin over normal but spin a lot longer and not even cough or sputter on the first attempt instead of being running within a second of turning the key. Then on the second try it would fire right up like nothing was wrong and run as usual so I just ignored it...
Then yesterday it spun and spun, like 10 seconds or more... second try, third try, fourth try, normal crank and spinning over but no attempt to start at all.
I had to be at work asap so I drove the MkIII Turbo Supra instead and finally took a look at the LS today and here's what I found so far...
Before trying to start it again I put the diagnostic jumper in and got a happy flashing CEL with no codes at all. I tried to start it and got lots of normal crank but no start again today like either spark or fuel was lacking...
I left the key on and inserted the jumper into the fuel pump pins, then a second later I heard a click and started hearing the flow of fuel into the fuel rails so that made me think the pump was fine and I assumed it to be a spark problem but decided to try the key again anyway just for the heck of it.
To my suprise he car fired right up in a second like it used to and began to idle for about 7-10 seconds as usual, then suddenly it slowly started losing rpm's like it was running out of gas that kept slowly dropping for 2-3 seconds, then it surged back up to normal idle for about another 15 seconds before slowly dropping rpm's and then surging back up to idle where it finally stayed like there was nothing wrong at all. I tried the gas pedal and it seemed to respond normally.
So I left it idling and opened the trunk and checked the "Fuel Pump Computer" connection with the car still running, wiggled the plug all around in its' socket on the computer which had no effect, banged on that computer with a screwdriver handle, banged on it hard with my hand, etc, etc, and the car kept on idling and didn't skip a beat.
So most likely either there's another relay in the chain (which apparently only the Cali models got?) or my fuel filter's clogged, or my pump's on its way out which I'm thinking is the case.
When I bought this car the used car lot had replaced the power steering pump right before I bought the car.
The week I bought the car with 184,500 miles on the odometer it got a genuine Toyota/Lexus timing belt, water pump, idler/tensioner pulleys, distributor caps/rotors, NGK Iridium spark plugs, thermostat, "Toyota Red" coolant, full tranny flush with the proper Toyota ATF, diff fluid change, full brake fluid flush with Mobil1 Syntec fluid, oil change with Mobil 1 Full Synthetic and Genuine Toyota/Lexus oil filter, serpentine belt replacement, new Lexus/Toyota front brake pads and "Premium" Wagner rotors (rotors were warped really bad when I bought the car), etc, etc, etc...
The valve clearences were also inspected (trying to find a tick but ALL 32 were still in spec and the tick is still a mystery) and new valve cover gaskets and related gasket maintenance parts and pcv valve/hoses/etc were also replaced in the process...
It also ended up needing an alternator last month but I think I drenched it in steering fluid several times so that's not the car's fault and the alternator that came off was a genuine Toyota alternator.
So it's gotten a pretty thorough going through and was totally drivable and reliable but obviously still not quite 100% right and I'm hoping the fuel pump is the culpret for this minor vibration and stumbling wierdness. I'll be suprised if it's not at this point...
NOTE:
There's a whole thread about an LS that won't tach over like 2,700 or 3,000 rpm's trying to find their problem. Some think it's the TPS (Throttle Position Sensor), others have replaced it and still had the problem and ended up with a bad Main ECU, and there are tons of theories with not so many actual solutions posted...
I've basically driven my car with its' minor random intermittent problems 50 miles each way to and from work, with a few minor annoyances and waited for them to become more apparent so that they could be found and fixed. The car has been totally freeway reliable up until yesterday and if I'd had a few more minutes to test things at the moment that it didn't eagerly fire right up I'm sure I could've gotten it started and driven it all the way to work and back as usual.
I'm sry, is it tomorrow already?