hot weather hesitation

[dfather99]

My pathy hesitates to accelerate on hot humid days. Once I get the pathy going it goes just fine and idles well at lights and takes off fine. but on that first start it acts like it is going to stall and I have to let it move itself. I've checked the Maf ground and cleaned the throttle body and air filter. On cooler days I don't have this problem. I'm thinking vapor lock? Does anyone have any suggestions or ideas if this is the issue or how to fix it.

[nztim]

I had an old car that had a similar issue and would have a shudder going on to, and after exhausting my options I replaced the airflow meter it went away.

[Precise1]

Check for condensation in your dizzy cap, a shot of WD-40 will cure it instantly but it will come back if you have a crack or poor seal.

 

B

[Tungsten]

Sounds like a MAF sensor or sensor wiring issue to me. When the oxygen sensor starts reading, the problem goes away.

[dfather99]

I checked the distro cap and Maf sensor again nothing changed. I was told to check the engine temp sensor as this will act like a choke any thoughts on this? Also I forgot to mention that the car idle fine it only bogs down when when I give it gas at the begining of my drive.

[andreus009]

Vaccum leak? Check the condition and secureness of the large hose after the MAF that goes to the intake manifold. Mine cracked all to heck and caused me to have some running issues. I do recall some hesitation on a quick accelaration from idle.

[Tungsten]

Vacuum leak is another really good possibility since nothing is monitored after the MAF sensor. The hose between the evap canister and the intake manifold likes to magically disappear by itself. Make sure you don't have that one missing.

[dfather99]

I'll check these and see what is going on

[NissanNismoZ]

Also..check to make sure your EGR valve is working properly and not sticking.. mine started doing this then it got to the point to where it wouldnt want to accelerate at all!