backfire loss of power

[Saitin]

was doing some work to it today. I had it at an idle for about 30 minutes and then it started sputtering. I started to drive it and it started to back fire, SEVERAL TIMES, more gas= more backfire. There is also a tremendous loss of power, and every time it hits 4000 RPMs it starts to stall.
none of the work I was doing was engine related(stero replacement,airbag installation)

[Camvill]

maybe you might have sucked up some water. It rained hard last night in hamilton. This happend to me awhile ago and about 2 days of driving it the water was completely out of the system. And it went back to normal.

[Saitin]

ok i'll let it sit for a few days then but it was running fine all morning then it just started backfiring.

[camaro2you]

Any gas/water in the oil?

[Saitin]

it looks/feels good to me can't see how any would have gotten in there.

[camaro2you]

Is it still running bad? When did you last get gas its possible you could of gotten a bad tank.

[Saitin]

still backfiring got gas same place I always get it and burned jsut over half a tank before it started backfiring

[98tadriver]

check engine light on? what do u drive?

[Saitin]

no light it is a 94 formula

[bubba428]

hows the fuel pressure? are you getting spark on all the plugs?

I would pull the plugs and see if any look like they where run rich/lean

[Saitin]

update been doing some internet research and a few things popped at me
could the optispark be causing this?

[bubba428]

yes but thats a venture you'd rather try not to deal with....try the cheap stuff 1st

[Saitin]

i'm going to look at the plugs tomorrow and see how they are
might just be time to change them hopefully!!

[JerzLT1]

yes but thats a venture you'd rather try not to deal with....try the cheap stuff 1st

cause youve done so many opti installs. it does sound like the opti, how many miles are on it? its really not too bad once you know what your doing, taking it off takes alot longer then putting it back on because you have to drain coolant and what not. they are expensive though. Alex went with a summit and has had good luck with it (they warrenty theirs) i went with AC Delco and have had good luck as well but no warrenty.

[98tadriver]

cause youve done so many opti installs. it does sound like the opti, how many miles are on it? its really not too bad once you know what your doing, taking it off takes alot longer then putting it back on because you have to drain coolant and what not. they are expensive though. Alex went with a summit and has had good luck with it (they warrenty theirs) i went with AC Delco and have had good luck as well but no warrenty.

+2 I didnt own a LT1 car, but ive helped out a certain someone with changing optis :lol: theyre really not that bad at all. just seems like it. get a friend to help or watch and youll be ok

[deadtrend1]

sounds like it could be a opti. Unfortunetly you have a non-vented so they are a little more expensive.

I would definetly get a fuel pressure guage on there first to see what your running at at high RPM.

[IROCdan330]

sounds like it could be a opti. Unfortunetly you have a non-vented so they are a little more expensive.

I would definetly get a fuel pressure guage on there first to see what your running at at high RPM.

agreed.

[Saitin]

aprox 160k on the opti
as for the gauge I don't ahve one nor know any one that does
any one near the hanilton area that can give me a hand?

[bubba428]

cause youve done so many opti installs. it does sound like the opti, how many miles are on it? its really not too bad once you know what your doing, taking it off takes alot longer then putting it back on because you have to drain coolant and what not. they are expensive though. Alex went with a summit and has had good luck with it (they warrenty theirs) i went with AC Delco and have had good luck as well but no warrenty.

I did two when I worked at pepboys....one on an f-body and one on a caprice. I use to be the only guy there Saturday nights.

[JerzLT1]

aprox 160k on the opti
as for the gauge I don't ahve one nor know any one that does
any one near the hanilton area that can give me a hand?

wow youve had really good luck lol. thats alot of miles for an opti. go to auto zone, buy a fuel pressure guage, use it, and return it. i did it and they had no problem with it. takes like 5 mins to check your fuel pressure. with those miles though i would really think its the opti though. you may want to consider swapping it out anyway just because of the miles on it. wouldnt wanna get stuck on the side of the road because of it. believe me it sucks

[ar0ck]

It most certainly sounds like an Opti issue. Way back when, when I started my Heads & Cam project, I replaced my 110k mile Opti with a Summit unit, the car wouldn't run over 3k RPM's and had the same exact symptoms as your car. I eventually took the Summit Opti off, to replace the cap & rotor with an MSD I had laying around for years. When I cracked it open it had all sorts of corrosion and junk on the points. I called up Summit that day, and they backed their warranty on the faulty part and had a new one at my door within a day.

I assume it was from moisture or something that caused the unit to fail.

I put the new Summit Opti-Base on with a MSD Cap & Rotor, with AC Delco spark plugs & wires and the car ran to the moon until I spun another bearing and FUBARED the motor :lol:

[Saitin]

fuel is good
so I am guessing I am having opti issues then any one have ballpark estimate on cost?

[JerzLT1]

400ish for a new opti? and a couple bucks for water pump gaskets. make sure you get 2

[Saitin]

ok then
I am going to see about taking the opti out and looking at it later or the next time it is warm again