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Discussion Starter · #1 ·
Ok guys...I've had 2 previous posts about this. I've searched all the threads and I'm still completely lost!!! I CAN NOT SEEM TO FIX THIS MISFIRE!!! I replaced my opti AND waterpump because it was believed that the waterpump had gone bad and drip onto the opti, causing the misfire and fouled plugs. Ok, fix that...same problem!

Noticed that my passenger side exhaust wasn't really kicking like it should, but the driver side was pumping hard...found out passenger side cat was plugged, thought that would fix it, bought a new one. SAME PROBLEM! And the passenger side is STILL not pumping out properly.

I have a very strong fuel smell in my exhaust, and my new cat is all discolored also, the plugs I JUST PUT IN A WEEK AGO are fouled out again, and smell like fuel too. Someone said I'm probably running rich! No idea how to check for that! WTF SHOULD I DO!!!!!??????
 

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Inspect all the fuel injector wires/ connectors and make sure all the wires are pushed in tight..

Does the car have any codes? if so post them up.

Does it miss when its cold and when its hot? Or only when it warms up? It could be an dead o2 sensor, (if they are orignal I wouldnt doubt it) fired wiring to the o2, stuff like that.

Also if its a 96, No one swapped around the o2 connectors did they? (sometimes when people remove the transmission they do this. )
 

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Ok guys...I've had 2 previous posts about this. I've searched all the threads and I'm still completely lost!!! I CAN NOT SEEM TO FIX THIS MISFIRE!!! I replaced my opti AND waterpump because it was believed that the waterpump had gone bad and drip onto the opti, causing the misfire and fouled plugs. Ok, fix that...same problem!

Noticed that my passenger side exhaust wasn't really kicking like it should, but the driver side was pumping hard...found out passenger side cat was plugged, thought that would fix it, bought a new one. SAME PROBLEM! And the passenger side is STILL not pumping out properly.

I have a very strong fuel smell in my exhaust, and my new cat is all discolored also, the plugs I JUST PUT IN A WEEK AGO are fouled out again, and smell like fuel too. Someone said I'm probably running rich! No idea how to check for that! WTF SHOULD I DO!!!!!??????
scan the car for codes.....or even better u know someone with a handy laptop to get a recording of what your car is doing?

any exhaust leaks?...vac leaks?...how fuel pressure....sorry i haven't read your other post but if state the whole story maybe troubleshooting over the internet would be easier.
 

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Dont panic yet. Look on the fuel rail behind the intake. When you find the fuel pressure regulator unplug the vacuum hose. If you have fuel in there the regulator could be bad and not regulating fuel to the engine. That would make car run super rich. Lmk what you find.
 

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Discussion Starter · #5 · (Edited)
"WHOLE" story....

That's the whole story. That's as far as I've gotten....New opti, new waterpump, new passenger side cat, 2 sets of plugs, that all fouled out (black and smelled of fuel), and 2 new flowmasters. I don't know which hose it was, but I took it off and replaced it cause it was cracked to hell, it also had a heavy fuel smell. It was the hose running from the "elbow" bend on the intake, to the top of the passenger side valve cover. I have no CEL. I took it to a shop but they couldn't give me a good reading on it cause its a '94, but from whatever bs they did check didn't throw any codes. And my passenger side muffler doesn't seem to be "blowing" like it should, and the driver side is "blowing" harder than it should.

Is only shuttering or "bucking" under load. But when I step on the gas it will go. It only happens when I take my car out of park and easy off the brake a little...kinda like when I'm just pulling into the garage...or easing up in traffic...OR...when I'm coming down to a costing speed after accelerating, Around 55....
 

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Discussion Starter · #7 ·
Would one of or both of those problems cause all my problems? The fuel smell in the exhaust, the discoloration on the cat, the fouled fuel scented plugs?
 

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Dont panic yet. Look on the fuel rail behind the intake. When you find the fuel pressure regulator unplug the vacuum hose. If you have fuel in there the regulator could be bad and not regulating fuel to the engine. That would make car run super rich. Lmk what you find.

i agree with the above

Would one of or both of those problems cause all my problems? The fuel smell in the exhaust, the discoloration on the cat, the fouled fuel scented plugs?
running rich causes the cat to heat up, heated up cat causing the discoloration, I think that is a result of the issue ur having not the issue its self
 

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Discussion Starter · #9 ·
10-4. So how do I check to see if I'm running rich? What's first? Someone even said my computer may be going bad. how much does on of those run?
 

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Sounds like the exact same problem I had. Misfiring, low power, passenger side exhaust popping, blowing out raw gas etc. After trying just about every possible solution, and even after checking my plug wires multiple times. I finally discovered that I had 2 plug wires crossed on the opti when I changed it.:eek:

I would triple check your plug wires.
 

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Discussion Starter · #12 ·
The ignition moduel....? 10-4...I'll check that too... Any more suggestions?
 

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Plug wires?

I didn't see it posted anywhere...
 

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Discussion Starter · #15 ·
I'll check my fuses. Any advice on how to check my O2 sensors?
 

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other thing you might check. look for dirty massair flow sensor. there is two little resestor lookin sensors in it. look from the air intake side. if they are dirty, u can clean with rubbing alcohal and que tip
 

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Random issing and down on power after opti change

My bud's kids car that I sold him had these same problems, No CEL's and ran like crap. Verified plug wires 10x, changed plugs 3x and a coil and a MAF and still no solution, threw out raw gas and still no codes, just timing all over the place at idle or off idle in park.

Solution, tore apart Brand new Delco Opti (Mexico Mfg). One of the two screws that hold the rotor in place had come out and the other was loose, so the timing on the thing was ALL OVER THE PLACE. Could not figure it out for a couple of days.

Returned it and got another one, checked tightness on the same two screws. They each got an extra 1/4 turn and it has been fine ever since 8 months ago.

Go figure brand new Delco replacement parts too.

Now why does my 95SS throw a module code after sitting for 9 months? And the module tests good at AZ? but misses like heck under load???????????????????????

Good Luck, the loose rotor was driving us nuts for a week and ready to scrap teh car till we found that one.
 

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Well somethings causing the car to turn rich if you smell raw gas. When was the last time you changed your o2's? I wouldnt bother testing, and just replace them if they're super old for preventative maintenance anyways. Unless you have a leak, im guessing its old o2's.

ps: If that dont fix it, Ill buy it off of you for the money in parts you just spent ;).
 

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Snakey I think postage on the car would kill your bank account.

O.P. It may be time to invest in an OBD-I cable and software since it appears nobody you know of has good stuff. This would allow us to see things like; are the O2's cycling evenly, is one bank considerably richer than the other, and what the commanded timing in park and low speeds is. I used my software to find out I had a very small leak at the cat to manifold gasket.

The software of choice is Datamaster (http://www.ttspowersystems.com/DataMaster.html) they allow something like 15 free runs before you have to purchase it.

For cables there are plenty of options. TTS Systems (see Datamaster) sell cables. I use one from pcmperformance.com. I'm sure a quick google search can find a few more options.

Good luck.
- Brian
 

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High fuel pressure makes all 8 run rich,. 1 bank running rich is determined by the O2 sensor,. if you have a vacuum leak and the O2 is reading too much 'air' it'll dump fuel in to try bring blms back into line etc,.
I had a problem one time and it turned out to be the "O" rings on 2 injectors on the 1 bank,. they weren't sealing right,. 1 had a split,. previous owner had changed the fuel rail and injectors and had hurt the seals,.
Your intake might be leaking check to see if the bolts are all evenly tight,.its a common problem with lt1's,
As was mentioned your O2 sensor on 1 bank might be fubar,..
and 5-7 wires can get mixed up easily too,.

Nick
 
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