Car hesitates to move from the stop sign.

[Slade901]

Car hesitates to move from the stop sign. Whenever I step on the gas while sitting from the stop sign, the vehicle hesitates for a second (as if the engine would die) and then recovers and runs fine.

This problem has been going for a long time. I've cleaned my IAC and even replaced the IAC and replaced the TPS. I've also done the Idle Re-learn and still the problem showed up.

I have to accept the fact that I could not fix the problem. My solution to the problem (at the stop sign) was to release my step on the brakes and let the vehicle move slowly without stepping the gas pedal for a few second and then push the gas pedal (that way the engine would hesitate and just move along just fine). Sometimes, if the vehicle is on a steep hill while sitting on a stop sign, I have to use my left foot holding the brake pedal and the right foot to put a little of gas while sitting at the stop sign and then release the brake pedal while putting more gas.

Yesterday, I was on my way to do my errand, I started the vehicle and it backfired once. Started again and the vehicle started but the Service Engine light came ON and the idle was bad. I though the problem would just go away once the engine warmed up. I tried to drive the vehicle slowly on the street but the engine is running badly and so I returned back home.

I’ve check for the stored error code and found 33 trouble code which shows MAP sensor and somewhere along the ignition system. I’ve checked the MAP sensor wire and it was fine and the vacuum hose to the MAP sensor is fine. It took me a while to find out that the vacuum hoses that connects on top of the throttle body was pushed out (probably when I have the backfire).

This vacuum hose comprised of a three vacuum hose, which is connected together as one and then attaches/connects to the top of the throttle body.

I reconnected this vacuum hose back to the top of the throttle body and started the engine and the Service Engine light turned OFF and the IDLE was fine and the vehicle runs fine (the hesitation problem at the stop sign is still there though).

I come to realize that this vacuum hoses is not very tight and can be easily pulled out. I was trying to find a way to secure these vacuum hoses to stay in place at the top of the throttle body and connected tight.

What I have come up was to use a thick aluminum wire and formed into the shape of ] and I just made two of them. I made the length of the wire just enough for it to properly pull in the vacuum hose and connected tight to the top of the throttle body. I then put a water hose clamp around the vacuum hose connector and the part of the throttle body to secure both the aluminum wire and the vacuum hose connector.

Started the vehicle and I soon realized that the engine does not hesitate anymore when I move from the stop sign. I even tried to put more gas while sitting at the stop sign when the green light lit up and the engine did not hesitate at all and it just moved the vehicle faster. No more hesitation.

The solution I have provided here might also solve some problem of our friend’s vehicle/engine hesitation problem when moving from stop sign. Try it to see if it works.

http://www.geocities.com/southbeach/...tle-body_1.gif

http://www.geocities.com/southbeach/...tle-body_2.gif

[DIY Mechanic]

Sounds good, I'll give this a try.
I suspected oil in the PVC line and was going to install an oil seperator.
Adjusting the idle up too much will activate the check engine light so I have not resorted to that.

I'll add to this post with my results on your suggestion.