91 Lexus Will Not Drive After Timing Belt Replacement

[2rotor]

I just picked up a 1991 Lexus LS 400 with 200,000+ miles on the chassis, only 68K on the engine. The previous owner had the waterpump, timing belt, and idler pulley replaced by a shadetree mechanic. Once put back together the car starts and idles without any issues. ALthough it will not drive. I got the car as part of a trade for a paintjob for his Escalade. ;) The front seats are a little rough but I think I did ok. Any Idea's on what might not be hooked up or why the car idles great but just will not pick up speed??

Thanks for any help you can provide.

[Ross W.]

Further information may be helpful. Does the engine respond to throttle input? Does the car go into gear when put in Drive or Reverse?

[2rotor]

Further information may be helpful. Does the engine respond to throttle input? Does the car go into gear when put in Drive or Reverse?

It has 0 throttle response at all, it will go into gear but when you mash on the gas it acts like the throttle isn't hooked up but it really is....

[cardona6569]

You need to clean or replace the Mass Airflow sensor which is located next to the air filter and change the filter if dirty. I think that is your problem, because when the car idles not enough air passes by the air filter, when it accelerates then the sensor works, it is either disconnected or not working or just plain dirty like it may be the air filter also, that may need change. Use electronic parts cleaner to do the clean up. Look in the Lexus forum of UK for tutorial of such. Make sure to let us know what finally cures the dilemma C. PR

I just picked up a 1991 Lexus LS 400 with 200,000+ miles on the chassis, only 68K on the engine. The previous owner had the waterpump, timing belt, and idler pulley replaced by a shadetree mechanic. Once put back together the car starts and idles without any issues. ALthough it will not drive. I got the car as part of a trade for a paintjob for his Escalade. ;) The front seats are a little rough but I think I did ok. Any Idea's on what might not be hooked up or why the car idles great but just will not pick up speed??

Thanks for any help you can provide.

[2rotor]

New Development!!!

I played around with the car a little more yesterday, found a vacumme leak, i fixed that.. the car will rev up a little more then it would before but still not enough to get the car driveable. Also I let it run for about 20 minutes and it started to smoke from down by the exhaust, it wasn't oil or coolant just smoke... After careful examination I noticed that the smoke was coming from the header on the passenger side, and it was GLOWING RED!!! The drivers side header was fine and not smoking at all.. Just the passengers side was red and smokey.. WEird huh?

Is it possible that when the timing belt was replaced the person had the Cam a tooth or so off only on the passenger side cam? would this cause the glowing header? Or is it something else?

I checked the MAF connection and it looked good.. Seems odd that the car was running great before the Timing belt/waterpump replacement.....

[Threadcutter]

New Development!!!

I played around with the car a little more yesterday, found a vacumme leak, i fixed that.. the car will rev up a little more then it would before but still not enough to get the car driveable. Also I let it run for about 20 minutes and it started to smoke from down by the exhaust, it wasn't oil or coolant just smoke... After careful examination I noticed that the smoke was coming from the header on the passenger side, and it was GLOWING RED!!! The drivers side header was fine and not smoking at all.. Just the passengers side was red and smokey.. WEird huh?

Is it possible that when the timing belt was replaced the person had the Cam a tooth or so off only on the passenger side cam? would this cause the glowing header? Or is it something else?

I checked the MAF connection and it looked good.. Seems odd that the car was running great before the Timing belt/waterpump replacement.....

2Rotor:

Is it possible that when the timing belt was replaced the person had the Cam a tooth or so off only on the passenger side cam?

Yes, very likely.

would this cause the glowing header?

Yes, very likely.

Don't run it anymore. With an exhaust header glowing red, you may have already caused damage to the valves, headgasket, exhaust gasket, etc for that cylinder. It's going to need to be torn back down, at least to the point where a good mechanic will be able to see the cam sprocket alignment marks and crank alignment mark to verify whether or not they all line up with their respective marks on the heads and block. Your passenger side valve timing is probably retarded by at least one tooth. The person that did your work apparently didn't lock off the cams before removing the timing belt? (!)

[JPI]

I just picked up a 1991 Lexus LS 400 with 200,000+ miles on the chassis, only 68K on the engine. The previous owner had the waterpump, timing belt, and idler pulley replaced by a shadetree mechanic. Once put back together the car starts and idles without any issues. ALthough it will not drive. I got the car as part of a trade for a paintjob for his Escalade. ;) The front seats are a little rough but I think I did ok. Any Idea's on what might not be hooked up or why the car idles great but just will not pick up speed??

Thanks for any help you can provide.

How is your timing? I would pull the timing cover. Roll it up to TDC and inspect for marks. If have you access to a scope, You will need to scope the wave pattern. Inspect the ignition also.

JP Importz

[2rotor]

I just picked up a 1991 Lexus LS 400 with 200,000+ miles on the chassis, only 68K on the engine. The previous owner had the waterpump, timing belt, and idler pulley replaced by a shadetree mechanic. Once put back together the car starts and idles without any issues. ALthough it will not drive. I got the car as part of a trade for a paintjob for his Escalade. ;) The front seats are a little rough but I think I did ok. Any Idea's on what might not be hooked up or why the car idles great but just will not pick up speed??

Thanks for any help you can provide.

How is your timing? I would pull the timing cover. Roll it up to TDC and inspect for marks. If have you access to a scope, You will need to scope the wave pattern. Inspect the ignition also.

JP Importz

This whole dual overhead cam deal is new to me.. I have previously only really dug into Rotary engines on Mazda Rx-7's. I am reading about how to set the timing now. It appears that when the belt was removed to replace the waterpump and idler pulley that the "mechanic" did not line it back up right. The previous owner claims that the mechanic had a lot of trouble getting it set. SO.... I am going to try to re-do it. My Father and I race miata's in the SCCA and he has set the timing on his 91 DOHC 1.6. It shouldn't be too much different... Thanks and any tips would be wonderful.

[dcfish]

I just picked up a 1991 Lexus LS 400 with 200,000+ miles on the chassis, only 68K on the engine. The previous owner had the waterpump, timing belt, and idler pulley replaced by a shadetree mechanic. Once put back together the car starts and idles without any issues. ALthough it will not drive. I got the car as part of a trade for a paintjob for his Escalade. ;) The front seats are a little rough but I think I did ok. Any Idea's on what might not be hooked up or why the car idles great but just will not pick up speed??

Thanks for any help you can provide.

How is your timing? I would pull the timing cover. Roll it up to TDC and inspect for marks. If have you access to a scope, You will need to scope the wave pattern. Inspect the ignition also.

JP Importz

This whole dual overhead cam deal is new to me.. I have previously only really dug into Rotary engines on Mazda Rx-7's. I am reading about how to set the timing now. It appears that when the belt was removed to replace the waterpump and idler pulley that the "mechanic" did not line it back up right. The previous owner claims that the mechanic had a lot of trouble getting it set. SO.... I am going to try to re-do it. My Father and I race miata's in the SCCA and he has set the timing on his 91 DOHC 1.6. It shouldn't be too much different... Thanks and any tips would be wonderful.

http://www.lexls.com/tutorials/engine/timingbelt.html

[2rotor]

Wow! Great link.. But let me ask you this.. Do I really have to do all that just to set the timing?

[VMF]

http://www.lextreme.com/timing.htm

did that job myself

let me know if you have any questions

that aligning is really tricky, if you dont set it right the car can even drive but it will perform very poorly

or just like in your case it might be drop dead.

btw do you have any check engine lights on?

yes you do, in order for you to check the marks on the tbelt and crankshaft pulley you have to take it all off

[2rotor]

http://www.lextreme.com/timing.htm

did that job myself

let me know if you have any questions

that aligning is really tricky, if you dont set it right the car can even drive but it will perform very poorly

or just like in your case it might be drop dead.

btw do you have any check engine lights on?

yes you do, in order for you to check the marks on the tbelt and crankshaft pulley you have to take it all off

The check engine light came on breifly then went off when I fixed the Vacume leak...

[2rotor]

Well I am getting ready to tear this thing down.. Hopefully no major damge due to the timing being off...

[TOYOTAPRO]

Well I am getting ready to tear this thing down.. Hopefully no major damge due to the timing being off...

Its also possible that he used a cheap gatorback timing belt from kragens or napa. The timing marks are very hard to align on the cheap timing belts. I recommend a genuine toyota one.

[2rotor]

Well I am getting ready to tear this thing down.. Hopefully no major damge due to the timing being off...

Its also possible that he used a cheap gatorback timing belt from kragens or napa. The timing marks are very hard to align on the cheap timing belts. I recommend a genuine toyota one.

Not sure which brand... I'll have to look.

[92Lex]

A gatorback brand shouldn't affect the alignment of the pulley's...unless he/she was given the wrong belt. If your cats were piping hot red and you lost power...it's most likely that your timing was accidently retarded. Ask me how I know. :whistles:

[swordfish]

to check timing you only need to remove air cleaner and piping, wire covers on both cam covers and one spark plug at no. 1 cylinder.

turn engine till a screw driver poked down no1 hole( right hand bank as looking into engine bay from the front) is at top dead centre( dont jam it against the sides)

and then check timing marks on cam gears are aligned with marks on the backing plate behind them. Look at lexls.com tutorial for timing marks.

Crank pulley should be at 0 mark as well. Doesnt matter where belt marks are as long as all above are lined up.

cheers

swordfish