ok, so my car has been sittin around for a year, no license. The motor was put in 4 days before i lost it... so it has a whopping 345 miles on it. the car was cranked and driven around the neighborhood once a week for just about the last 12 months.Being that I get my license back next week I am just making sure everything is working on it. Today I take it around the neighborhood, runs fine. Take it on side street, open it up, burns em through 1st, into second..get to about 4500 and it starts to backfire, then loss of power... i pull into neighborhood, seems to drive alright in 1 & 2 gears... pull into garage, runs about 2 mins, surges some from 400-800rpm.. almost like its gasping, then it stalls out. Now it wont start up. Turns over, like its about to crank, then nothin. I dont get it. Pulled the CAI off and there is some white smoke comin out the intake manifold, smells like exhaust. It threw the SES light, tho I dont kno what for and prolly wont for a few days till I can get it scanned. The opti has been replaced in the past, tho I am thinking it may be the culprit. I did notice a small coolant leak coming from a cracked hose that i fixed the other day, possibly it leaked onto the opti some? only after the car has been up to speed does it get on the opti causing this problem? Im open for suggestions

 

Exhaust out of the intake. Timing chain??

 

timing chain is brand new, and set by the manufacturer. Doubt its that. Exhaust in the manifold is probably from the backfire in the exhaust itself.

 

Fuel pumps love to go bad on cars that sit, especially fuel injected ones. You car sounds like it ran out of fuel..........check the filter first then suspect a bad fuel pump.

 

Start by putting a fuel pressure gauge on it. See if your pressure is right. Being that the car sat a while, that opens you up to a world or possible problems. I would put the fuel pump at the top of my list based on what you said. If it's that the code will most likely be a cylinder misfire code on one or all.

 

sounds a lot like a lean backfire(out the intake instead of exhuast) to me, my bet is on fuel pump.

-Mark

 

My car did the exact same: when cold it starts up fine, minutes later it surged and gasped, backfired ext... it threw a code(coolent temp malfuntion/ high input) after shutting off the car it would not start unless the gas pedal was mashed all the way down, then ran like ****. after consulting many people, everyone said it was either my opti(which was 1 month old) or my mass airflow. well to my surprise i purchased a $15 coolent temp switch along with new plug thats all on the waterpump. Problem fixed, no more falling on its face, backfiring, gasping, smoke ext... the temp switch tells the computer that the motor is cold, if bad: results in dumping of fuel and map codes out the ***(running like ****) if i were you i would check this out b4 anything, i rather pay $15 than $300




1996 camaro z28SS car#1656

 

I had the same symptoms on my car and i had a coolant leak that got on the opti and that was the culprit... I say its probably opti related..... Good luck. I am on my 3rd opti...


Chris

 

yah, when i got home last night the car cranked right up. I am going to say its either that sensor or just a leak on it. I think I will replace all the hoses and that sensor and just be on the safe side

 

My 94 did that two, fuel pump.

 

It's still sounds like fuel pump for me (or may be filter clogged)...

 

fuel pump and filter are good. Car cranked right up last night, as well as this morning. I am thinking its a small coolant spray on the opti.. the car literally pissing on the optispark.

also noticed my o2 wire draggin the ground, wires most likely shorted out, that would throw the fuel ratio off on 1/2 the motor... flooding it out no doubt, Im going to try taking both 02s out here in a few mins, see what happens... I kno this has happened before, 02's shorted out and car didnt go nowhere...