GlobeCLK

iTrader: (5)

Hey guys,

For the past couple of weeks my throttle has been weird.

Say I'm cruising on the freeway at around 75mph, foot off the gas pedal. When I step on it to accelerate, the car would not move for about 2 or 3 seconds. Then it will start to accelerate. It doesn't suddenly surge forward like the tranny stopped slipping. It feels like the car is reacting to my throttle command a few seconds late.

This would happen once every 3 or 4 times of acceleration. Sometimes the lag is shorter, sometimes the lag could be as long as 3 or 4 seconds. It's really dangerous when I tried to accelerate when changing lanes, but the car would not accelerate while I change lane.

I resetted my ECU last week. After the reset, it was gone for a few days. But now it's back again.

I checked the pedals, checked the throttle cable, no problems there. Can someone give me some advice on what this could mean? Thanks!

GWELEX

For starters I'll suggest cleaning the the throttle body. Could be the throttle plate is sticking.

JMgs300

I brought my car to the dealer last week because of the same problem. They said it was something with the ECU and it was covered under warranty. So far it feels like its fixed because it hasnt happened again... but yea i agree its very scary. I was pulling out of my neighborhood one day and needed to get on it a bit so i didnt get T-boned and it hesitated on me and scared the ***** outta me!

PHML

iTrader: (33)

Did you add any additive to your gas lately?

I would do the following.....continue to use Premium Gas (high Octane), add Fuel Injection Cleaner to gas then fill up, clean Throttle body, clean MAF sensor, clean Air Filter, reset ECU, check transmission fluid levels, etc.....

Good luck.

Pete

GlobeCLK

iTrader: (5)

Thanks for the help guys, I'll try to get my throttle body cleaned ASAP.

Pete,

my bro gave me a bottle of the FI Cleaner today and I added it during fill up. I always get Premium gas.

I'll follow up after I try some more steps. Thanks people.

btw how hard is it to reach the throttle body? It looks pretty deep inside the whole intake manifold part.

GWELEX

Can't say for a 300, but on the V8's once the intake piping is removed it's right there, very easy to get to. Take great care cleaning the MAF sensor, very delicate.

Fisher503

Did you re oil you intake recently?

David1969

Yeah if you recently re-oiled your air filter (provided it's a K&N, or the like) then you may be over-oiling it and there is gunk accumulating on your maf sensor. The throttle-body would be my first move though as far as cleaning it to try and solve the problem.

For some reason when i'm playing with the throttle, i almost get the feeling it's a fly-by-wire type of system due to the way it reacts. Part of me likes that, the other part of me says it's gonna be a PITA to figure out when something goes wrong.

GlobeCLK

iTrader: (5)

gwelex,

Yah seems like the V8s' are right there in the front. For the 300 I know where it is but seems like it's deeper inside the metal. I'll have to check.


fisher and david,

I washed and re-oiled my K&N Filter 2 weeks ago. However I had this hesitation problem at least 3 or 4 weeks before I did that, and the reason I washed and re-oiled was because I thought it might be the dirty intake.

But yes, I'll definitely check out the throttle body first.

David1969

Ah HA! I'd start with the MAF sensor first then. That thing may be gunked up and may be screwing with your air/fuel mixture which is why you have the hesitation.

GlobeCLK

iTrader: (5)

thanks a bunch for the info

GlobeCLK

iTrader: (5)

UPDATE:

Guys, today I tried the CRC MAF Sensor cleaner. It's good stuff. The MAF sensor on the GS300 looks very different from the conventional MAF sensors out there. There's a protective housing on the whole sensor, shaped sort of like a jetplane's engine unit. I was alittle hesitant on spraying the cleaner because I wasn't sure if it was what I was looking for. But flashlight into the unit showed the wires, so that must be right.

Anyways, sprayed it and cleaned it. The cleaner drys very fast, I would say completely dry in under 30 seconds. After reassembling the intake, I immediately feel a difference in RPM climbing speed and throttle response. However, I can't test the hesitation problem unless I get on the freeway, and I did not have time for that.

So tomorrow on the way to school I will have about 30 minutes to try it out. If the MAF sensor cleaner really solves this problem, it would be great.

David1969

Keep us posted. This is good info.

GlobeCLK

iTrader: (5)

OK guys here we go.

I drove all day today, spent about 1 hr and 30 minutes on the freeway. Initially when I got on the freeway and did some driving, I still felt the serious hesitation, maybe 4 or 5 times. Later on, it got a lot better. Usually when I let go of the gas and then step on it again, it would lag and hesitate. It was much better now, but I still feel it alittle bit.

After 4 hours of school I got on the freeway again. Again when I just get on the freeway, I feel some of the hesitation (but nothing serious, maybe 1 second or 2.) And then after a bit of driving it got barely noticable.

So yes the CRC MAF sensor cleaner definitely helps, I don't know if it will fully cure this problem yet, but it definitely got a lot better. I will be resetting my ECU tonight, and report back tomorrow night on the results of driving after the ECU reset.


CRC MAF Sensor cleaner, good stuff.


btw, if any of you guys get this "low RPM idle" when the car is cold, this MAF Sensor cleaner fixes that. For the past 2 months when I start my car in the morning, it would start at around 1200rpm and then quickly dip to around 600~700rpm. This MAF Sensor cleaner got rid of that as well.

GWELEX

I didn't read where you cleaned the throttle body. That last bit of hesitation could be there. The sticky black goo that builds up in there could be causing this, once the engine is warm it thins out, thus works a little better. Not sure if you have drive by wire, but until you learn how to make it work, there will always be a hestitation there.