patches1612

Hi guys, My 1985 vette is running like crap still. I bought it from a buddy last year . He had it sitting outside for a long whille and the gas tank filled with water. I replaced the fuel pump, gas filter, injectors, adjusted fuel pressure to 38 psi, spark plugs, coil , IAC, Cap, wires EGR valve adjusted TPS to 0.54 volts and it still has a miss. I installed Accel 24lb injectors in place of the 22lb. stock ones. Are 24lbs too much? It has no codes, and it uses gas like crazy. The fuel average is 6.2 miles per gallon. Not sure if I should replace the injectors again or not. Mileage on the car is 62,000 Any Ideas?

BSenzina

Stop throwing money at it and get it to a GREAT MECHANIC ! !

PLRX

Accel Injectors...

I tried those and put the OEM back in the 95 Vette. That was long long ago like 2005. The Vette idled like crap and I sent them back.

I bought a set of Bosch III from FIC for my 96

http://forums.corvetteforum.com/c4-t...ea-or-bad.html

patches1612

Wasn't throwing money at it. The whole fuel tank was filled to the top with water. Thanks for Nothing.

patches1612

Thank You, PLRX. I have heard bad things about Accel injectors

James93LT1

When you install a different size injectors, you have to have your ECM retuned.

F22

Many of us here got our injectors from FIC! Did you also replace the fuel filter as well?

patches1612

Yep replaced the fuel filter too. I replaced all the fuel system components because the fuel tank was filled to the top with water. It leaked down the cap

John A. Marker

First of all, the stock injector for the 85 is 24 pound. I have run Accel injectors without problems. They were recommended by a good friend that has a Corvette shop and is extremely well know for his ability to repair and custom tune Corvettes. He has experienced no problems with all the cars he has installed them in. You should be averaging much more than 6 MPG. I am getting 30 MPG on the freeway running all the modifications below. What does the exhaust pipe look like? Are the plugs coated black?

Have you tested the fuel leak down pressure. Attach you pressure gauge to the fuel rail, turn on the key and what pressure do you get? Does the pressure hold or drop. If it drops, how long does it take to go from say your 38 lbs to 15 pounds?

Did you blow out the fuel lines with compressed air when you drained the tank?

Are you using the GM stock chip? Is the car stock or modified?

Frizlefrak

Beat me to it.

Since your mileage is in the crapper, it's doing one of a couple of things....burning a lot of fuel, or leaking it. If you've ruled out leaking it, that leaves burning it. So why would a modern EFI system burn too much fuel?

1. The PCM is telling it to. Why would it do this? Maybe the PCM believes the engine is cold, and therefore needs a richer mixture. Is your thermostat good? Any chance the car is staying cold and thus running a rich mixture? What about the Coolant Temp Switch? Any chance the car is heating up, but it's sending an erroneous signal to the PCM?

2. The PCM isn't telling it to richen the mixture...but an injector or 4 are leaking. Do the fuel pressure leakdown test suggested above. The fuel rail should hold pressure for several minutes. Another possibility is a grounded injector that's hanging open all the time. What do your plugs look like? All fuel fouled, or just a couple of them?

3. An ignition problem is causing an incomplete burn. I know you replaced a number of components, but are we missing something here, like an optispark issue maybe? Yeah, I know, the opti gets blamed a lot, but sometimes it's guilty.

4. A faulty PCM. Perhaps an injector driver or two is hung closed, and the PCM is opening the injector to full pulse.

We need to know leakdown time of fuel pressure, ignition system health, and what EACH plug looks like. Get that and report back.

patches1612

Thanks guys. I will check those things and pressures and get back to ya

Leftoverture

Might check the evaporative emissions canister, too. Could be that is full of water.

msledge50

1985 does not have an opti spark

Paul Workman

Well, NOW yer gonna hear some GOOD about the Accel injectors

I've got 16 of 'em and she idles smooth as silk, great traffic manners, screams like a banshee... What not to like????



P.

Nathan Plemons

They say even a cow misses it's *** every now and then.

I don't have Accel injectors, but I never will. I have heard infinitely more bad about them than good. In fact the two people on this thread who say they have no problems may be the ONLY 2 people I've ever heard say such a thing.

In all seriousness, if your injectors are suspect you can take them out and have them tested / flow checked, etc, etc. I know that's not the easiest thing to do on a TPI, but it would tell you for sure.

BSenzina

Didnt mean to upset you with that....What I meant was....now that you have replaced soooooo much in an attempt to resolve the problem, get a mechanic to troubleshoot the problem, rather than change out more parts needlessly. Good luck

mtwoolford

there can't be too many ways that that much gas is getting into the engine. check to see if the vacumn line from the fuel pressure regulator to the intake manifold is full of gas; if so the fuel pressure regulator diaphram is shot and providing a direct path for fuel into the engine.

allautomotive

I have accel injectors on 2 of my vettes and have no issues. I have also installed many sets on customer cars and not yet had an issue relating to the injectors themselves. I have had people with contaminated fuel systems that consequentially messed them up however. Most people are replacing injectors because there are already having issues, mostly due to lack of maintenance, rusty tanks, bad fuel etc.... This is a bad starting point for a customer review on a product.
I would start with pulling out the spark plugs as mentioned and inspecting them as they will tell the story. If its a bad injector as mentioned above, this will tell you which one or at least be a starting point to a proper diagnosis.

patches1612

Thanks guys for all your great help and ideas. I now have renewed enthusiasm. To fix the problem. When the weekend comes I am going to try all your suggestions. I have been working two jobs and always have to wait to work on the car. I will keep you all in tune of my progress. Thank Younagain for the help