drd21968

i purchased a 91 383 ,superram,bought new accell injectors,completely tuned up,could not get it running right .took it to my friends shop.cant find a sensor or a wire for the sensor its not the mas air flow any way the car had computor problems and still does.the remedy my mechanic suggested ditch feuel injection replace with intake and carb eliminate the computor woes.what do you guys think

Muffin

Carbs served well for almost 100 years so it would be foolish to say they are no good. Any NASCAR track is proof the carb is alive and well. But FI provides a much broader range of engine performance than a carb, cleaner too. I think you should find a more competent mechanic.

emo-vet

i thought 1991 vettes had m.a.p sensor set up, Not mass air flow sensor ???
cheers
shae

CFI-EFI

You have a mechanic who is not equipped to work on your car. He suggested changing to a carb because he doesn't know or understand EFI. Find someone qualified to work on EFI, or better yet, order yourself some books, plus the FSM and become that person. Don't make your car take a step backward just because the mechanic won't take a step forward.

RACE ON!!!

billybonesmusic

the setup you have is a good one, but i will trade you a carb for it

naaaaa J/K get the manual, and with that and this forum, you can fix it right. i will not trust "mechanix" anymore, no one will treat your car the way you will.....

93-383

If your FI is fubar a carb setup would be cheaper 4-700$ for intake, carb, and incidentals. The other option is replace the entire wiring harness and computer with a PAINLESS system about 1k$

CFI-EFI

Cheaper? Are you sure? How can you possibly know what it will cost before it is diagnosed? Is the replacing of "the entire wiring harness and computer with a PAINLESS system" really "The other option"? Especially if there is nothing wrong with either of them? Good advice.

RACE ON!!!

wayne lowry

You should FIX your car not destroy it. Without knowing what is actually wrong with your car suggesting you scrap the FI and run a carb is absolute nonsense.

bogus

the 1991 needs the engine controller to feed the CCM, which feeds the dash it's info.

Don't hack it with a carb.

You are close enough to a larger city to find a competent tech to fix it.

pipe

I thought my Injectors were bad also and had problems with the car starting and not starting running rich anyway the guys on the forum told me to check my coolant temp. sensor (sounds stupid) After replacing bunches of stuff it was the sensor $12 bucks JUST A THOUGHT Pipe keep us informed

SHINOBI-X

I wouldn't suggest going toilet bowl injection. Do some searchs on the topic and what it intails. Your 383 superram should run good and no reason you should ditch EFI to go to carb.

P.S. implanning on adding EFI to my blown chevelle,can't stand the cold morning starts and insonsistant A/F ratio im always getting. I'd suggest try and learn to trouble shoot the problem and get some hands on experience with working on your vette.

drd21968

it was a map sensor he was refuring to.no wire for it he said the car thinks its cold without the sensor.i got this car cheap and i think the reasoni did the previous owner had computor problems and got frustrated with car.the mechanic said he could fix it but wiring in car has been played with and he said it could get costly .i hate to get rid of feuel injection ithink its a good set up the dyno sheet with car had it around 390 rwhp.the previous owner spent a fortune at a speed shop on car with computor control problems .i dont want more problems going with the carb.has anyone done this and were there any complications. thanks

jmrl98

Don, if you use the search function you can look up the EFI-carb swap. But you really ought to re-read the responses within this thread.......

billybonesmusic

in your origional post you asked "what do you guys think?" not "how do i replace the FI with a carb"! so everyone thought you should work out the FI, but you want to swap.....so.........If I were you, I would start ANOTHER thread and post that question.

CFI-EFI

This guy keeps proving his ignorance. It is the engine coolant temperature sensor, not the MAP sensor, that could make "the car thinks its cold". With no MAP the car thinks it is in outer space where there is no air pressure. When the MAP fails and there is no signal to the computer, the computer substitutes in a fixed MAP value and then uses input from the TPS to control fuel delivery. It sounds as though the mechanic is making excuses to justify not fixing what he knows nothing about. In itself, that is a good thing. He could really mess it up if he doesn't know what he's doing. Do some studying and fix it it yourself or get it to someone that can work on EFI.

The previous owner spent a bundle on this stuff. It would be criminal to just throw it away.

"it was a map sensor he was refuring to.no wire for it he said the car thinks its cold without the sensor." INDEED!!!

RACE ON!!!

FD2BLK

You my friend have an idiot for mechanic period. Read CFI-EFI's last post it is spot on. No codes to tell us about before scraping the FI system? The ECM diagnostics are there for a reason and your EFI challenged "Mechanic" should know this but from reading his solution to what ever problem you have it sounds like he is more of a hack then a technician. There are many who have converted to a Carb for many reasons, some legit some not but telling a customer to swap to a carb because a Technician is uneducated in fuel injection is borderline criminal IMHO

93-383

The previous statements about the car thinking is cold due to a detached coolant temp sender wire are incorrect unless the computer defaults to OOS low instead of OOS high on infinite resistance. The coolant temp sensor is an RTD if no feed voltage is passed though ad returned to the source the computer will se infinite resistance.

CFI-EFI

The OP made no mention of a detached "coolant temp sender wire". See post #12. He said the "it was a map sensor he was refuring to.no wire for it he said the car thinks its cold without the sensor.". I was the one that mentioned the ECT sensor as the device that would make "the car thinks its cold without the sensor." So far, the ECT sensor isn't involved in this problem... that we know of.



Not that it is relevant to this OP's problem, but actually they are correct. As per your statement, "if no feed voltage is passed though ad returned to the source the computer will se infinite resistance.", and since greater resistance is "seen" as colder temps, infinite resistance would be viewed as "the car thinks its cold without the sensor." Try again?

RACE ON!!!

93-383

its a pretty basic concept on how a RTD works resistance increases as temp increases if resistance is infinite then temp is out of sight high. This is not a thrmo-couple pyrometer where measurement is caused by dissimilar metals generating low source voltage the higher the temp increases. In that case you would be correct. But since nearly all temp sensors on an engine are RTD (resistance temperature detector) their value of measure is based on the resistance generated due to heat. And I would advise keeping that tone in off-topic where it belongs.

CFI-EFI

In this case I am correct. First, the function of the ECT sensor is not germane to the discussion at hand. But if it were, your gobbledygook about RTDs, thrmo-couple (sic) pyrometers, and other off the subject devices don't pertain to our Corvettes. Try reading the FSM to learn about your CAR, if you plan to discuss it. Here is a cut from my FSM that may enlighten you.



Is "Off Topic" where you usually introduce discussion that is off the topic being discussed, like you have, here? Or where you, incorrectly accuse others with the correct info of being "incorrect", by citing "Off Topic" references? I am not familiar with "Off Topic", which is the reason I ask.

RACE ON!!!