AYEOH5.0

hey guys sorry for not updating at all this weekend, i spent the weekend at my girlfriends and she doesnt have a computer >< anyways, i emailed the guy i bought the car from about the problem, and this is the answer he gave me.

"If the decel/clunking is at low speeds/low rpms, it is due to the cam at lower rpms and the computer sometimes gets confused with the decel maps because of the overlap and it wanting to cut fuel on and off from the cam overlap. It doesnt do it at higher rpms like if you are at 2K and above. If it were a mechanical issue, it would do it all the time. The trans mount is new. I believe the rockers are 1.6 roller rockers, but that I am not sure of. I never had the valve covers off, so I do not know. If not, maybe throw on a set of 1.6 or 1.7 roller rockers. Glad you are enjoying the car!"

nacanitihs

what cam do you have in it again?

vristang

What he's telling you is probably the right direction, but the details he's giving are a little sketchy....

Low speed bucking is typically from LOAD error. The cam isn't usually directly responsible for this (in my experience anyway), but it can contribute if there is some overlap (which creates injector timing issues).

If all of your parts (ecu, MAF, & Injectors) are properly matched, then a custom tune will take care of it... or at least improve things dramatically.

To verify the MAF, ecu, and injectors are properly matched....
What color are the injectors? Blue, Orange/Yellow, Red, ????
What are the part numbers/Brand markings on the MAF meter? A pic might be handy too....
What ecu??? Pull the passenger side kickpanel and drop the ecu. There will be a sticker there that will have a ton of part numbers on it. You are looking for something resembling A9L, A9P, X3Z, A3M, A3M1, etc....



Because of the answer you recieved from the previous owner, and how it was worded... I would start with the parts verification.

Also, it would be worth the time to run through the diagnostic codes to verify all the sensors/wiring are functioning properly.

Let us know what you find,
jason

AYEOH5.0

i know it has red top injectors, and i think he told me it had a maf from anderson motorsports.

edit : heres duration and lift on the cam

crower 234/240-533/544 roller cam

393strokervert

I have a similar problem in my 95 Gt 393 stroker 5spd, it kicks at low rpm's , 1,400rpm's & below when trying to hold steady or decelerating in gear. only happens like when I am driving through a parking lot at slow speeds. haven't had much time to check it out yet as I have only owned it for about a month. first thing that I am going to do is to clean the mass air & other air related sensors & check for any stored codes .

mjr46

verify the parts if it's efi!!^^^^^my 347 does the same but it's carbed, below 2k it bucks on decel, I've yet to tune the carb which will take care of a lot of the issue

393strokervert

you might want to try checking your timing. I have a 91 notch with a carbed 302 in it & I had the same problem. my timing marker was off causing me so set the intial timing on the "retarded" side so I just advanced it 2* at a time until it went away.

mjr46

^^^^it's not timing in my case, everything was degreed in and is dead nuts on, mine is a result of the huge overlap on the cam, it is a very healthy custom cam

vristang

Typing on a phone so this will be blunt.

I would love to help, but I can't give advice bsaed on what some guy might have told you maybe

you need to answer the questions.....