Engine hesitation!!

**99blueZ** · 07-05-2006, 10:05 PM

I have a '99 Z28 6spd with 74k on it. I have some sort of problem with engine hesitation. It usually happens when i am excelerating slowly with light throttle. Usually between 2000 to 3000 rpms is the problem. I never have hesitation above 3000 rpms. This happens in all 6 gears. When i am at WOT the car is great and has no power loss. I have had the problem for a few months now and since have changed a few things but the hesitation is still there. - plugs/wires, pcv, air filter, oil/oil filter. So rule those things out. I do not have any ses light on.
Thanks!

Pepe LePew · 07-06-2006, 05:08 AM

might want to have that throttle body cleaned

**99blueZ** · 07-06-2006, 04:33 PM

my next mod is going to be port and polish of my throttle body - so maybe that will fix it.

**~redlinels1~** · 07-06-2006, 04:35 PM

Try cleaning your MAF.

**99blueZ** · 07-06-2006, 04:56 PM

i regularly clean my maf so that shouldn't be it but thanks

**cobra12345** · 07-06-2006, 05:40 PM

my 00 ss does same thing all new filters on it im gonna check fuel pressure next you find out wsup with it let me know thx

**swimster144** · 07-06-2006, 08:49 PM

Yea, keep us up to date with what you try, cause I have this EXACT problem as well. I tried replacing my fuel filter and that didn't help. So anything that helps...let us know.

**99m6t/a** · 07-07-2006, 11:36 PM

I also have this problem (however mine does it at any throttle position)

I have changed plugs, wires, fuel filter, cleaned MAF, and checked the Air filter....... Its still there

I'm going with the 02's or cats being bad next

I have a question for u guys could it be a fuel pump going out and not sending enough pressure to the injectors (just trying to hit all angles)

**Orcus79** · 07-08-2006, 08:27 AM

could also be the injectors or a injector.

**swimster144** · 07-08-2006, 11:19 AM

Originally Posted by 99m6t/a

I also have this problem (however mine does it at any throttle position)

I have changed plugs, wires, fuel filter, cleaned MAF, and checked the Air filter....... Its still there

I'm going with the 02's or cats being bad next

I have a question for u guys could it be a fuel pump going out and not sending enough pressure to the injectors (just trying to hit all angles)

I dunno, the fuel pump could be a good idea, but since I only really get the hestiation at part throttle, I'm not so sure that would be it, but who knows...

**cobra12345** · 07-08-2006, 12:12 PM

ok this is what i did i looked at my tb and i noticed some slack in my cable so i adjusted it and now where the bump stop is its not sitting on the tb anymore its about 1/16th off the resting point car idles at 700 after wram up and theres no slack in my cable seemed to help me out dont know why it wouldnt sit on the resting point though maybe the spring on the cam is worn you guys try anythingelse let me know

**99blueZ** · 07-09-2006, 07:40 PM

ok - so i just finished changing my fuel filter. I drove it around and it barely ran

I think i got some air in my fuel system. I purged it again and i let it idle for a few minutes and then drove it. The more i drove it the better it felt - so i think i drove the air out of my system. BUT it is still no better than before i changed the fuel filter. The car still hesitates like crazy.

**99blueZ** · 07-15-2006, 10:34 PM

ok guys the car is fixed!!! Had a local performance shop run my car on their software and it showed my fuel system was fine thus its not and injector problem. So we said that it must be the MAF. So we out in a SLP 85mm MAF and WOW!!! My car runs perfect now. No hesitation - no bogging - runs great! And my car has never felt faster. The old MAF made the car run like crap but i never realized how bad it ran. It is so much more powerful now.

**swimster144** · 07-16-2006, 08:54 AM

I wonder why the problem only came up now, maybe its cause the old MAF was just getting old and not reading as well...maybe I'll try getting one of those.

**NinerSevenTango** · 07-18-2006, 04:20 AM

Oil fouling from a sponge type air filter?

**drdon51** · 07-23-2006, 12:02 AM

http://www.ls1.com/forums/showthread.php?t=24042 had the same problem just cleaned my maf wrong

**swimster144** · 07-25-2006, 06:25 PM

Ok, so my hesitation is completely FIXED!! I put in the SLP 85mm MAF and the hesitation is 100% gone. Thx for the help 99blueZ.

**99blueZ** · 07-25-2006, 09:29 PM

No problem - glad it helped you out!

**wolfews6** · 07-29-2006, 03:57 PM

Originally Posted by swimster144

Ok, so my hesitation is completely FIXED!! I put in the SLP 85mm MAF and the hesitation is 100% gone. Thx for the help 99blueZ.

Where do you buy the MAF (are they expensive??) and is it easy to install??

Try to solve the same issue,

Matt

**illcul8troffcr** · 07-30-2006, 12:28 AM

Originally Posted by wolfews6

Where do you buy the MAF (are they expensive??) and is it easy to install??

Try to solve the same issue,

Matt

Ebay killer hahah its the best place and cheapest.. get it from a reputable seller though.. good positive feedback..

SLP is not good on price discounts overpriced actually.. Granatelli makes a MAF thats supposed to be good as well and their a sponsor on the site here so maybe contact them and see if they can work a deal .. if they would I think I might be changing over as well