IH8FORD

iTrader: (6)

I know that accel injectors are not the most popular choice but have they been known to give problems.

JonCR96Z

iTrader: (33)

I just don't believe that there isn't any 02s. You've actually seen the hole where the O2s go and it was empty? It should be right on the collector of the headers (where all the pipes come together). And you're positive that you're not talking about the rear O2 sensor. Without O2s, the drivability of the car would just be ****. It never would have had power to lose.

pyronotic138

iTrader: (1)

k everyone is missing the point i am trying to make. the point being that one day FAST as **** and another slow. and yes it has drag setup on the suspension. i dont own the car but i do the work on the thing and just trying to get help on what caused it to lose power "just like that". vacuum is 28-30 in HG.

also when this thing shifts from 1st to 2nd at WOT. it feels nutless. i agree that whoever put that 700r4 in needs to get the input shaft up their ***. the computer operated valvebody is better than a throttle opperated valvebody. IMO. anyone help please. i just need to know how to diagnose what the problem with the thing is. how to test **** and what to start at.

JonCR96Z

iTrader: (33)

You can't diagnose **** properly if you're not sure what it has and what it don't have. And there is the one goof ball trying to disprove that it runs 11s.

pyronotic138

iTrader: (1)

ya. i admit it doesnt run 11s. but it did. i have seen 383s that ED Wright has tuned that were NA cars that were in the 9s. anyway. there are o2 sensors the flat 4 prong.

in what steps should i go about checking things. i have checked fuel pressure, vacuum,

i know i need to check compression, then change the oil definately, what other stuff will get me closer to a solution

96capricemgr

iTrader: (1)

My point with doubting it is an 11 second car is the info we are getting about it is unreliable therefore we have little chance of helping. Kid said 11 seconds flat(to me that is 11.0) and that he beat a car that ran 11.04, his friend said it ran 11s.

28-30inhg is wrong. Stock is only 21 and a performance cam only makes that number go down.

Accel injectors are supposed to be better now but in the past were known to leak fuel inside and out, guys have had cars burn down. There were sets bad enough to cause this problem.

From what I am reading the whole car is a train wreck that is going to take major effort to sort out, I honestly hope it is bad info we are getting and the car is in better shape. Much easier for an owner to learn than it is to have to rebuild a car.

JonCR96Z

iTrader: (33)

If you can't get around the fact that people in general don't know **** about cars, then you shouldn't be trying to help. I mean it's obvious that he doesn't know what it runs and he don't know what it has. Which is why you ask questions that will lead us to the right answers. Kinda like talking to a woman about cars.


And just to give my experience with the matter. If you didn't run it down the track and see what times it runs, then you don't know.

JonCR96Z

iTrader: (33)

Ok, thats enough with the 11 second ****. If it ran 15.4, now it runs 17.8 its the same difference. It don't matter.

Well at least we know that it has O2s, now. You said you thought they were bad, did you give em a visual? If the spark plags look like **** then the O2s probably do too, and though it might not have cause the problem it ain't helping. So unless they look brand new, go get you some new ones. Don't get Bosch, by the way.

ATAY383

hey 96capricemgr if ur not gonna help me figure out my car then dont post anything anymore go bug someone else im trying to figure it out so i can take it to the drag strip so then i know what it will run.. for know yes i dont know **** about my car but **** im learning more about it.

JonCR96Z

iTrader: (33)

I say if the oil ain't milky and the cylinders don't leak down, then check the O2s. Replace if necessary. Then see how it runs.

Maybe the coil went bad, caused the plugs to foul. Which made it run rich as **** and knocked out an 02 sensor. My CTSV did something similar after relocating the MAF.

Speaking of which you don't happened to have a K&N filter thats recently been re-oiled do you?

Jon

ATAY383

i will change the o2 sensors and i will check out with the filter.

Alex94TAGT

Whew! Ok, well I'm glad it's got oxygen sensors (the 1994's only have two).

We know the car is running pig rich. Either the oxygen sensors are reporting accurately and the computer can't physically stop the fuel from dumping into the engine, or the oxygen sensors are shot, reporting lean, and the computer is adding fuel for the 'false' lean condition it sees.

1) Probably not the cause, but you might take a look at the coolant temp sensor in the waterpump housing. These are simple thermistors, which vary resistance in a reverse relationship to temperature. As such, when they fail, they will permanently tell the computer that the engine is negative 40 degrees, so the computer dumps in fuel to help warm up the engine.

2) You said the fuel pressure tested out fine (-what was it, specifically? Stock is around 42-47psi without vacuum applied to the fuel pressure regulator). Furthermore, did the fuel pressure hold when you shut off the vehicle? It should. If it doesn't, it's always possible that the fuel injectors are junk, or are otherwise locking up and dumping fuel into the engine. If you suspect this, you can always pull up the fuel rail, prime the pump, and see if any injectors are leaking. Might also check injector resistance (-should be around 12-15 ohms for high impedance injectors, which this car presumably has).

3) Not a major point, but what method were you using to determine vacuum -- a mechanical vacuum gauge, or by the MAP readings? The standard barometric pressure on any given day in Kansas is about 29"Hg -- if you truly had 30"Hg vacuum, your MAP readings would be in the negative. I'd test it again, because what you've found isn't mechanically possible. For comparison, my 383ci made 20~22"Hg vacuum at idle, and I was surprised it was that high. (=MAP readings around 7-9"Hg at idle.)

4) There was something else I was going to say, but forgot! Grrr...


Doesn't sound like you have datamaster or anything, which would really come in handy here. Datalogging is a million times better than throwing parts at the car. You can try cleaning the oxygen sensors with brake parts cleaner and/or a propane torch, but if you do replace them, replace both with AC Delco. As mentioned, Bosch sensors have caused issues in our vehicles.

ATAY383

how much would it cost for a datamaster and do u guys think it could be a oil pump.

Alex94TAGT

1) Why are you thinking it's the oil pump? That's out of left field. Was your oil pressure gauge reading low recently? Either way, you've apparently got fueling issues, which of course would not be associated with the oil pump. If you're having oil pressure problems, for heaven's sake DONT drive the car until it's fixed. Check for metal shavings when you change the oil.


2) You wouldn't have to buy Datamaster -- I believe they (still) allow ~20 free datalogs before you have to pay. Problem is you need an ALDL cable to connect a laptop computer to the DLC port under the dash, which can cost upwards of $100 depending on where you go.

Since you have a 1994, another option is the Scanmaster LT1, which is a simple box you can mount on your dash and has LED readouts of the PCM, albeit it's not a datalogger. I have Datamaster and the Scanmaster, and love them both.

ATAY383

well thats what one guy told me was to check that.. god man that car is such a ******* problem i guess i should of bought a reg z28 and built a 383 then i would know what im dealing with.

ATAY383

oh yea this guy that tuned my pcm said when he was driving my car. that my car was running open loop. and something else but i dont remember what all he said.

FASTFATBOY

iTrader: (23)

Coolant temp sensor is really the ONLY sensor that can cause what is happening, change it and see.


The one in the water pump.


David

96capricemgr

iTrader: (1)

This is why you have a heaping pile of **** in the driveway. There are kids who will stroke your ego and there are guys who will be blunt about telling you when you are wrong, only one of those groups will help you learn what you need to fix and maintain a highly modified car.

I have offered several points. Like the MAP point that Alex made, your MAP reading is local barometric pressure, that aint right.

pyronotic138

iTrader: (1)

i will check the oil and see whats up. prolly change the header gaskets becuase they are blown out. then check visually the o2s. if they look good then i guess whatever. i am going to change the coolant temp sensor on the water pump. at least people are helping a fellow fbody owner. i know these motors and cars but dont know this much in depth ****. also the car has a brand new tuned pcm. the tune is the same setup that it was running nice with

pyronotic138

iTrader: (1)

anyone else