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U

UB2 SLOW

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I replaced my old opti, plugs and wires when I pulled the engine. The car is still not running right. I changed the 58mm TB for the stock 48mm and the Ram Air. I changed the BOSCH plugs for the NGK's and I rechecked the Taylor wires. The car runs better now, but it is still not running right. It idles high and the ECM keeps putting out lean codes. I changed the fuel pressure from 44 through 47. Ed Wright recommended 47. I still get lean codes. I am now going to swap the new opti for a newer opti and see if there is a change. If this does not work, I am going to shoot the engine with my shotgun. :r Okay so maybe I wont. :(
 

JT ZR-Won

Well-known member
Joined
Dec 6, 2000
Messages
1,291
Location
Bradenton, FL
Corvette
'90 ZR-1 #3010
:hb
I know the aggravating feeling you have. I have definately been there before. Are the internals of the motor modified at all?? When you say it's not running right, what exactly is it doing?

With a little more detail as to what the car is doing some good suggestions will come up.

Jay
 
U

UB2 SLOW

Guest
I have threads for the problems posted. It has eradic idle, eratic power curve between 5000-5800 rpms and an overall lack of power. It is also running lean. I am not too concerned with the lean part right now. I have put allot of bolt ons, onto the car and had it reprogrammed from Ed Wright. If the changing of the opti works, great, if not I will have a back up opti.
 
Joined
Jun 20, 2002
Messages
2,509
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Tallahassee, FL
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none right now :(
Go back to square 1 with the fuel pressure first... you are running a stock TB, which will limit you on your power... I still think the bigger injectors are dumping in fuel, but it isn't getting enough air to handle it... also, the O2 sensor may be fried from all the tuning/excess gas... check the O2 sensor before you buy a new opti... I seriously doubt the opti is bad.
 
U

UB2 SLOW

Guest
I have just ordered a 52mm. Hopefully this will fix most of the problem. I will have to wait until the weekend to check the O2 sensors.
 

69MyWay

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Jul 3, 2001
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Auburndale, Florida
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1969 Killer Shark
ARe you sure you don't have a vacuum leak on the brake power booster, emissions lines, vacuum check line to the opti, or a bad PVC valve?

Go back to the basics first.

When you say you have a lean code, are you running a stand alone scanner, or are you paper clipping the diagnostic and reading the flashing check light?
 
U

UB2 SLOW

Guest
Its a stand alone. I have rechecked everything about 3 times. If I am missing something I do not know where. I am not as concerned with the lean problem as I am with the eratic idle and lack of power. The loss of power between 5000-5800 rpm is what I am really concerned with. I plan on going through everything again tonight.
 

poorboys831

Well-known member
Joined
Nov 1, 2001
Messages
146
Location
charleston,s.c.usa
Corvette
1993 ruby red coupe
hi ub2slow,if you need a buyer for that opticrap give me a chance at it i need one or will for my '93 -hope you your problems fixed-dennis :w
 

69MyWay

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Joined
Jul 3, 2001
Messages
4,364
Location
Auburndale, Florida
Corvette
1969 Killer Shark
UB2 SLOW said:
Its a stand alone. I have rechecked everything about 3 times. If I am missing something I do not know where. I am not as concerned with the lean problem as I am with the eratic idle and lack of power. The loss of power between 5000-5800 rpm is what I am really concerned with. I plan on going through everything again tonight.

Are you getting spark retard? Maybe your Knock sensors are picking up too much noise and kicking your timing back causing bad idle and acceleration.

You should be able to see that on the scanner.
 
U

UB2 SLOW

Guest
My Scanner is one of the Cheap ACtrons. It is not showing a knock.
 

BigRed

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May 23, 2001
Messages
948
Location
Edmonton
Corvette
1985 Bright Red Rocket
Along with the O2's I didn't see anyone suggest that the sensors them selves are fine BUT are you running your Cat Converters still? If you have pulled them your O2 sensors will do whacky things.

If they are still there and are in good condition perhaps the amount of motor your running and/or the extra exhaust is making them freak. Or simply put they are just bad.

In any case, I would put the cheater plugs on the O2's and then you won't have to worry about that particular problem and your ECM will be goofed into thinking everythings normal.
 
U

UB2 SLOW

Guest
I do have stock cats. Do the cheater plugs affect emissions?
 

BigRed

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May 23, 2001
Messages
948
Location
Edmonton
Corvette
1985 Bright Red Rocket
Probably the ECM will not see the "Gunk" blowing through the tail pipes. Therefore your gonna fail. Someone chime in if Im wrong but Im 90% sure thats the way it is.

Im guessing emissions are a problem.... Mabe something can be redone with programing your ECM perhaps.

The only reason I suggest the plugs is because your "choking" the engine with faulty computer read-outs Also the fact the cats are still on is probably hurting you as well.
 
Joined
Jun 20, 2002
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Tallahassee, FL
Corvette
none right now :(
poorboys831 said:
hi ub2slow,if you need a buyer for that opticrap give me a chance at it i need one or will for my '93 -hope you your problems fixed-dennis :w

'96 opti won't fit on '93 without other modifications... just thought I would let you know before you bought the wrong one


-the O2 sensor cheat may make you fail, but only if things are not running properly.... worst case is, you put the O2 sensors back to stock for emissions... Try searching around the internet on the topic, i know you can get the parts from radio shack for only a few bucks, and at the very least it will help you isolate the problem.
 

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