I started about 2 months ago with my car stumbling and stalling out in the rain. So cheap things first, and I changed the Plugs and wires. That didn't help. So I went out and got and opti. Problem fixed. Then the car had touble starting......Had the starter test 3 times and it tested fine. But for some reason my car would start fine if I pressed on the gas a bunch of times(turned out it was just enough to move the starter enough to get it to start). Well I drove it around for about a week like this. Then the I stopped at the gas station, and I tried to start it, I had a lot of trouble starting but got it started. After that I drove the car and it stumble a bunch like it was missing. I changed the starter and got it to start fine, and just changed the plugs thinking I had fouled one. Well the stumble went down, but it is still there. It seems like it will hit 2300, stumble and then at 2500-2700, it will kick in with a burst of power. I have no clue. In the process of everything else I have also changed the TBS, water pump. thermostat, radiator, and the ignition coil. I NEED HELP!!!!! What else can I try? I have put some much money into my car and have gotten no performance upgrades. I need some help What could be causing this?

 

sounds like an opti. maybe someone with more insight can help more.

 

1. Make sure intake elbow is connected secure to the TB and MAF without 'folding over itself' and causing an air leak. This is VERY common at the TB (on bottom side). This is very suspect because the intake elbow was obviously removed when the Opti was replaced.

2. Run a bottle of Textron FI cleaner through that bad boy.

3. Check the ignition coil (a stretch)

4. Check vacuum lines for a possible leak, or disconnect.

5. EGR, PCV - vacuum lines connected?

6. Fuel pump? Sh!tty gas station?

Sorry for not hitting the nail on the head, but misses can be caused by a hundred different things. Hope this helps.

 

Are you still having a hard start problem? If so you troubles may be the Fuel pressure regulator. Just another thing for you to look at. YOu can go to a garage and they can hook up a fuel pressure test gauge on your adapter on your fuel rail.

 

Thats what i would do my friend had the same troubles and it ended up being his vacum hose.

 

That sounds similar to my oxygen sensor induced problems. Quick and cheap fix too.

 

I checked the fule pressure and it is fine. The starts are great. It is weird cause it will give me that stumble, then like kick in, and the power is back. Is there a way to check for a vaccum leak? The elbow is fine and on there all the way around.I just checked it. I ran some seamfoam through there about 3 weeks ago. Things were great until this start problem, and it was an almost instant stumble problem after I stopped to put gas in, but that tank of gas is gone, so it wasn't the gas. Would this be an oxygen sensor?

 

thats no O2 sensor. if you fuel pressure checks out fine then you might be experiencing opti failure. ever get SES light?

 

no SES light. Bought a code reader from Autozone, and it isn't giving me any codes. It's a brand me OPTI too. Only about 400 miles on it.

 

i had very similar problems when i had a fouled left o2 sensor.

mike

 

I had the exact same problem as you, stalling out in the rain back in '96. Also ended up with the same problem.

I replaced checked and replaced everything simple, gathered diacom data etc...

In short this is what happened to me:

1. Coil wire corroded initially, caused the car to stall in the rain. Trying to restart the car would cause it to backfire, eventually it would start again. Went the the dealer, fixed the wire under warranty
2. The backfiring and detonation or possibly the coil wire itself crapped out the optispark. Replaced it and noticed an improvement, car still didn't feel like it did before the problem.... ran it like this for 1 1/2 years.
3. The backfiring and detonation caused unburnt fuel to enter the cat, effectively poisoning it. Also the air pump died at one point (before the recall) both of which contributed to a partial meltdown. I found this out quite by accident when I installed my Mac headers and y-pipe. I cut the y-pipe off of my cat just out of curiosity and found the cat was severely melted and the intake, causing restriction in the exhaust flow. This would actually get worse as the cat warms up to operating temperature. (which explains why the cars run well cold until they warm up).

So for me, the optispark and a partially plugged cat was the cause of my low rpm hesitation.

 

with the power kicking back in after in stumbles, it sounds like an O2, a friend of mine had this stumble problem where he would give it some gas and it wouldnt accelerate properly, and then the car would take off like he revved, all at constant throttle

 

well, first off, it ain't the cat because I have nothing in mine. I took it on the Highway today, and when it was in 6th at less than 2000rpm, the car was shakeing like crazy. Once I got it to about 85 mph, it stopped shaking. I am noticing a total loss of power through out all rpms, and it really isn't kicking back in. Just at high rps it isn't as noticable. It isn't just between the 2000-3000 mark. The wires look to be good, and I might go get another set since they are LT warranty. I also dropped the idea that it is an 02 sensor since I have no SES light coming on. Anymore ideas.

 

burnt plug wire or cracked/fouled spark plug. after doing headers my car did the EXACT same thing and it was all caused by 1 or 2 burnt wires.

 

Did the plugs last night and checked the wires. Wires looked fine....nothing was burnt