AR's LSnotch

Hey guys I need help is a 93 gmc rally can wit a tbi 5.7 . Van was working perfectly fine out of no were it wouldn't wanna idle once u turn it on ... So I drove it 3 miles but wit my foot on the brake an other foot on gas ... So I replaced the I.A.C an still does the same once u start it won't idle . Now I changed the map sensor an temp sensor an no diffrence .... I replaced the spark plugs cus they were all black haven't changed them in the last 9 years .. I changed egr wit one I had at home an nothing so I put bak the original bak I adjusted the idle an I got it to stay on an run once u in gear but wen under load it misfires terrible but once u get on it a lil more it stops missing an runs good .... I noticed at idle I put my finger on the egr diafram I rev it an it dnt open the egr is controlled by ecu so wen is under load it should open

I work for a shool district I'm a mechanic but just on disel am new to gas this van is a school vehicle

So can someone help me here I been working on this for 3 days an is a headache

crainholio

iTrader: (2)

I understand your situation but this topic isn't relevant here...the only thing your engine has in common w/ LS engines is the rod bearings.

Might get good results here: http://www.gm-trucks.com/forums/

AR's LSnotch

I kno is not a LS motor but was in need of help of a problem in a Chevy motor that's why I ask'd cus I kno thers alot of people here that work on those motors

crainholio

iTrader: (2)

I stopped reading after that. Not even an Internal Engine question to boot, more of a diagnostic issue. Wrong forum of the wrong board.

99 2500

Sounds like the timing chain jumped a tooth, if it has a lot of miles this is very likely the problem. Use the performancetruck.net forums, that era is covered there.

AR's LSnotch

Yes it does have alot of miles an I will check the timing see if its off ... I removed the o2 sensor an is all black so its running rich .... I cleans it out an put bak an same thing happening .... But ill check timing

Thanks man not like other dude I understand wat he means but all I was asking is for help ...

That's not hard to do

crainholio

iTrader: (2)

Neither is spelling correctly, and yet...

PREDATOR-Z

Well, that is the product of our educational system. The thing that always bother me is that they get upset when I request some order and not chaos (posting in the right forums).
That is one reason why I believe in mandatory military service, that teaches people discipline, organization and planning.

00ssmg

iTrader: (4)

I will make a quick comment to help you out. I would put money on it that the van has a week fuel pump. TBI set ups will run with low fuel pressure but like garbage. DOUBLE and TRIPLE check fuel pressure before you do anything else

schnellttz06

Hmm, interesting. So who would pay for that? And im assumimg you never spent a day in the military. Some things cant be taught.

PREDATOR-Z

LOL, if you only knew.....

schnellttz06

Well, I dont really need to know.

PREDATOR-Z

Sometimes ignorance IS a bliss.

schnellttz06

I guess you live a blissful life then

crainholio

iTrader: (2)

Buuuuuuh Bye