Acceleration after starting

[ddr81]

I've got a 2006 Vibe, base 1.8l engine, 210,000-ish miles on her. Lately, when I start it, regardless of outside temp, it won't accelerate. I have to let it warm up a bit, and turn it off and back on, then after a couple of tries, it will accelerate as normal. And when I saw won't accelerate, I mean i can push the pedal to the floor and barely registers an RPM change. I was getting a TPS code, so I changed that. Cleaned the MAF, checked for vacuum leaks. Alternator is new, battery isn't but isn't testing bad. Only other code I am getting is P0452. I'm thinking fuel filter/pump, but thought I'd ask you fine folks!

[andrewclaus]

Worn throttle body?

Did you have the same symptoms before changing the TPS?

[ddr81]

Thanks for the reply! I replaced the whole throttle body with the TPS, so it's all new. Seemed to get a tad better rigth after replacement (this was only a couple weeks ago) but really symptoms have stayed the same.

[andrewclaus]

If you can "reboot" it after it warms up and it runs fine, I don't see fuel being the problem. Unfortunately, there's no test port.

Will your scanner give you pending and past codes?

Maybe a vacuum leak that seals up with a warm manifold? Do you have a vacuum gauge?

[ddr81]

Could be, I'm thinking I'll have no choice but to take it in. There are also times, like yesterday morning, when the car starts, cold, no issues, and accelerates. Very confusing.

[lexicon]

Was wondering on if there was a resolution.
A few years ago I cleaned my MAF sensor and decided to clean it by lightly using a Q tip and the correct spray solvent for MAFs. I ended up damaging the very delicate sensor, I found a "new" one on Amazon and all was normal again. Two years later, I started having acceleration issues, stumbling engine RPM at start up and poor gas mileage and after properly cleaning the MAF, I still had an issue. I ordered a new Denso MAF from Rockauto and when I compared the supposed exact same part, noticed the printing was not quite the same as the "genuine" Denso part. I believe I got a counterfeit and it did not last past 2 years old. I now only order important parts thru RockAuto.