Kahunah911

Okay, I've been wrestling with this 90 that has sat for 7 years. I've been chasing all kinds of loose or dirty connections. I got everything that wasn't working squared away, except I can't get it to run.

I have a good spark, injector pulses. fuel pressure and compression. The strange thing is the plugs are dry. I've been cranking on this thing for days and they are still bone dry. If fuel is being delivered and it hasn't started they should be wet. There is no fuel odor at the tailpipe either. The car literally sat covered for 7 years. The fuel pump was shot. New AC Delco fuel pump, cleaned and flushed the lines and a new filter. The injectors ohm out, all are right at 17 ohms.

All grounds are good. Scan tool shows no VATS issue (and the security light works as it should, it cranks and as I said it has injector pulses on both banks) and I have even tried a known good ECM.

To me it can only be the injectors, but it's hard for me to wrap my head around all 8 injectors being stuck or plugged closed. Any one ever have this happen. Any other ideas?

red89c4

i would squirt some fuel in the TB while trying to start it and see if it will start. if it does this will at least tell you that it is not getting fuel. i feel as if you already know that it is a fuel problem but this is a simple test.

don hall

This link may help (?):

http://forums.corvetteforum.com/c4-t...-1990-l98.html

bassackwards

Have you checked to make sure you actually have fuel at the rails and injectors?

UNCLEBILL

Also you must still have the original Multec injectors as the specs cold are 16.5 +/- .5. My old Multecs on my 1990 were never that close but fuel injector cleaner has a way of changing the specs .
Good luck
Bill

aklim

If it were my car, the Multecs would already be in the landfill and not just the trash can. Still, for curiosity, I would check pressure at the rail and test for whether it holds pressure or not.

blackozvet

good advice from the guys above, remember that injectors are electrical and mechanical , just coz they ohm out ok does not mean they are ok, the pintle valves that open and shut could be stuffed !
a set of rebuilt bosch 3 injectors are only $170.

85corvettec4

those bosch's are smooth as butter

aklim

Or as was said in Heartbreak Ridge, smooth as a prom queen's thighs.

Kahunah911

I ordered a set of the Bosch III injectors. I guess I'll know for sure then. Everything else checks out. Fuel pressure checked with a gauge and fresh fuel at the schrader valve when the gauge is connected, have spark, injector pulses verified with a noid light both banks, all are 16.5-16.7 ohms, no VATS issue on the scan tool, tries to hit with fuel sprayed in the throttle body. And as stated the plugs are bone dry.

I have never encountered all the injectors being plugged, but then I have never had anything sit for seven years. The tank was a mess, the original fuel pump looked like something from pre-historic years and it was almost sludge that came out of the fuel lines when I flushed them. I assumed the fresh fuel in the lines would dissolve anything left but maybe the injectors are too small and fragile to deal with the residue.

On the bright side there will be nice shiny Bosch injectors in there.

aklim

I am assuming that you did a pressure test to see what it was when you turned on the engine but not crank, right? They also held pressure after shutdown, right? What is the condition of the pump? Did you change the filters and the pump sock filter?

JrRifleCoach

Just reminded me of parading the the local HS girls around on our Vettes recently.

Ahh what were we talking about?....

Kahunah911

Yes, pressure tested, new AC Delco pump assembly, new filter. As much as I have been cranking on this thing if fuel was being delivered and it was an ignition or mechanical problem the plugs should be wet. It has injector pulses and fuel pressure.

aklim

College girls and I might give them a ride id there is a chance that they will let me ride them after the ride.

skyhawk50

FIC saved the day for me! Less than 1/2 hour to install them on my 92 and car runs like (better than) new.

aklim

Here is what I want to know. Turn the key to run and see what pressure you get. DO NOT CRANK. Turn key off and see how long it takes to bleed down.

Kahunah911

@45psi and it holds. I've walked away from it and came back about 2 hours later and it was at 25psi.

aklim

That is a but of a drop. I would crimp off the return line and see what happens

aminnich

Possibly take out an injector or two, hook them up and then turn the engine over and see if they are spraying gas?

DanielRicany

Before You Install The Injectors, Like The Other Guy Said, Instead Of Fuel Though, Spray Starting Fluid In Your Intake, If You See A Response From The Engine, You Are Dealing With Fuel Delivery And I Would Then Replace Injectors. If You Get No Response, I Would Check Timing.