Auomatic Car Doesnt Move Till I Push The Gas

[Chizzim Smith]

hello, my lexus is200 auto doesnt move when i put it on Drive till i step on the gas. It is meant to have some momentum when in Drive before the gas is pressed. Also the car idles low at about 400-500rpm in drive. any ideas to as what the problem might be?

[noby76]

it might depend on where you park! if you park on a slightyly uphill then chances are it will not edge forward when you first stick it in D but that momentume will be used to hold the car sliding backwards hence it doesnt move forwards. test this by driving to a flat surface road or a downhill road stick it in P or N start and stick it in D the minute its in D quickly take your foot off the brake pedal and see if it edges forward! so long as transmission is shifting ok and smoothly i wouldnt worry too much bout it. Also when was the last time it had a fluid drain and refill? had mine done in Feb buy Albin B Motors (Lexus/Toyota) specialist in London using the recommended Toyota Type -IV oil and seems to be shifting more smoothly but this was because my car had done over 100,000 miles so thought it was due a drain and refill although Lexus said it was a Lifetime oil didnt believe it. worth having this done but make sure no other oil is used but Toyota Type T-IV as anything else will cook the Transmission. cost me £206 all in for transmission oil , differential oil and brake fluids change from Albin B motors if that helps...

[Chizzim Smith]

thanks for the reply, well its definitely not due to a slope because it does that on flat surfaces as well, i drove my friends is200 auto and the difference was clear. I also noticed that mine idles low at 4-500rpm while my friend's IS idles at about 1000rpm, can this be an issue?

[steve2006]

The tickover speed does appear to be low (my V8 is 650rpm) so that is probably the reason why yours does not "creep" when in drive.

Tickover spped is normally determined by the ECU but a dirty throttle body or incorrectly set up throttle pot sensor (TPS) can also cause low idle speed. There could be other causes besides those mentioned.

Try turning the AC on, this will normally raise the idle speed and then see if the car creeps in drive.

[chrisgixer]

What Steve said ;)

[Rich OB]

It could also be a sticking caliper.

[TigerFish]

It could also be a sticking caliper.

Ditto that as an additional check.

[Chizzim Smith]

thanks for your replies guys, well i just cleaned the throttle body and car was fine again, RPM increased to 1000 and car now moves better, seem to have gained a couple of horsepower as well.. :zee:

[ridgersIS300]

Sorry to bring up an old(ish) thread, but where abouts is the throttle body and what do you use to clean it?

[north]

carb cleaner or brake cleaner (the last one is very aggressive) but both do the job.

the throttle body is easy to find just follow your air intake it goes straight to it and because you are going to need access to it you'll have to remove that anyway.

[ColinBarber]

carb cleaner or brake cleaner (the last one is very aggressive) but both do the job.

the throttle body is easy to find just follow your air intake it goes straight to it and because you are going to need access to it you'll have to remove that anyway.

I'd be careful with brake cleaner, a little too aggressive. It could do damage to the TPS and MAP sensor

[north]

carb cleaner or brake cleaner (the last one is very aggressive) but both do the job.

the throttle body is easy to find just follow your air intake it goes straight to it and because you are going to need access to it you'll have to remove that anyway.

I'd be careful with brake cleaner, a little too aggressive. It could do damage to the TPS and MAP sensor

true! hence my warning... But if all else fails there are more options.....

Carburettor cleaner the best option

WD40 can be used as a cleaner no harm to sensors but will leave oily layer behind

Brake cleaner not recommended as it can harm sensor

Diesel bath with brushes as a cleaner to breakup big carbon buildups and after that, you'll need to use the dishwasher if you want to get it clean throughout you'll have to use water repelling stuff after it comes out, carb cleaner is your best option for this, but it does the trick, this is the way you could do it when you are going to do a complete engine rebuild and want every part as clean as possible the cheap way. This is not recommended for beginners ! very time consuming but will give an almost new unused look to the complete throttle body and it's internals)

PS do not forget to get new seals for the throttle body as every removal can damage the air tight seal of it.