Fuel Delivery issues?

Suicide Bobb
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I don't want any "tl;dr", so here's the short:

When I shift and let out the clutch, then give it throttle immediately after, my car will hold the rpms for about one second or so, then accelerate. It almost seems like it didn't grab the gear, and then all of a sudden it's good to go. Power delivery also is not especially smooth, meaning when I hold a constant throttle, it feels akin to a gear in the transmission that has a few sheared teeth (but it is like this in every gear).

Also, when I do a cold start and continuing on until the car warms up, the rpms waver down a few hundred rpm, and then back up again, in what seems like a distinct pattern. It's similar to a vacuum leak, but the "up-down" intervals are more spaced out. Once it has warmed up enough, it stops.

I was told that the latter issue was the IAC, which controls the choke in order to properly warm up the car. This makes sense and hopefully will either totally disappear or get better after I clean the throttle body and the sensor.

While the former issue feels like a clutch issue, I have a strong feeling it isn't because it doesn't slip when going uphill, or when I am full throttling it and hit a rut in the road, and I would think that the issue itself would involve not a lag in the rpms, but a rise in the rpms and a lack of movement. A local mechanic thinks it's a clogged fuel filter, and told me to clean the injectors and throttle body, run a tank of gas through it, and then change the filter. He says that the lag is from the system building up enough pressure to where it gives in and operates normally again (not his exact words, but you get the point).

Do both of these diagnosis make sense, as well as the attack plans? I think I'm gunna hit it with some fuel injector cleaner and clean the TB/IAC tomorrow, but I want to know if the fuel delivery system is even a probable cause of my two issues.

 
but the lag problem seems like your transmission is sticking.. thats what I got from reading that. the IAC problem is most likely the problem with the inconsistent rpms, but you know cars, nothings ever that easy.

 
but the lag problem seems like your transmission is sticking.. thats what I got from reading that. the IAC problem is most likely the problem with the inconsistent rpms, but you know cars, nothings ever that easy.
Soooo true! I don't know how my transmission could be sticking though...it's a manual btw

 
I don't want any "tl;dr", so here's the short:
When I shift and let out the clutch, then give it throttle immediately after, my car will hold the rpms for about one second or so, then accelerate. It almost seems like it didn't grab the gear, and then all of a sudden it's good to go. Power delivery also is not especially smooth, meaning when I hold a constant throttle, it feels akin to a gear in the transmission that has a few sheared teeth (but it is like this in every gear).

Also, when I do a cold start and continuing on until the car warms up, the rpms waver down a few hundred rpm, and then back up again, in what seems like a distinct pattern. It's similar to a vacuum leak, but the "up-down" intervals are more spaced out. Once it has warmed up enough, it stops.

I was told that the latter issue was the IAC, which controls the choke in order to properly warm up the car. This makes sense and hopefully will either totally disappear or get better after I clean the throttle body and the sensor.

While the former issue feels like a clutch issue, I have a strong feeling it isn't because it doesn't slip when going uphill, or when I am full throttling it and hit a rut in the road, and I would think that the issue itself would involve not a lag in the rpms, but a rise in the rpms and a lack of movement. A local mechanic thinks it's a clogged fuel filter, and told me to clean the injectors and throttle body, run a tank of gas through it, and then change the filter. He says that the lag is from the system building up enough pressure to where it gives in and operates normally again (not his exact words, but you get the point).

Do both of these diagnosis make sense, as well as the attack plans? I think I'm gunna hit it with some fuel injector cleaner and clean the TB/IAC tomorrow, but I want to know if the fuel delivery system is even a probable cause of my two issues.
IAC stands for intake air control, it controls the RPM of your vehicle when you're vehicle isn't moving. Engine temperature has nothing to do with it.

Remove it, as well as the throttle body & spray them down w/ a degreaser. (you gotta clean the hole in the t/b this sits in or it won't make a difference. Also, be careful not to twist/push on the IAC when you clean it....it will screw it up.

might be a good idea to disconnect the battery before you re-install it....that way the PCM resets & wipes out the ****** idle memory.

 
but the lag problem seems like your transmission is sticking.. thats what I got from reading that. the IAC problem is most likely the problem with the inconsistent rpms, but you know cars, nothings ever that easy.
if it has wires, wheels or boobs its gunna give you problems

 
IAC stands for intake air control' date=' it controls the RPM of your vehicle when you're vehicle isn't moving. Engine temperature has nothing to do with it.
Remove it, as well as the throttle body & spray them down w/ a degreaser. (you gotta clean the hole in the t/b this sits in or it won't make a difference. Also, be careful not to twist/push on the IAC when you clean it....it will screw it up.

might be a good idea to disconnect the battery before you re-install it....that way the PCM resets & wipes out the ****** idle memory.[/quote']

Thanks for the help!
 
Sounds like you already got some good advice. My first line of attack would be to change the fuel filter, clean fuel injectors, and clean the tb and intake manifold. Seafoam that bish.

 
Ya, looks like these guys gave you all the right advice. Man I miss carburetors....

I'm having a similar problem with the idle RPM's as well, does it whether its warmed up or not. I'm hoping its just the auto choke //content.invisioncic.com/y282845/emoticons/confused.gif.e820e0216602db4765798ac39d28caa9.gif

Anyways, GL!

 
Sounds like you already got some good advice. My first line of attack would be to change the fuel filter, clean fuel injectors, and clean the tb and intake manifold. Seafoam that bish.
Well the reason you should replace the fuel filter last is that if you replace it, then knock all the crap off the injectors and what not, it's just going to clog up the new filter.

But yeah, seafoam wouldn't be a bad idea. I already seafoamed my engine internals (oil related stuff), and then my oil pump just so happened to decide to fail the next day...

 
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Suicide Bobb

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