|
10-24-2006 | #1 |
Join Date: Oct 2006
Location: jacksonville, florida
Posts: 43
|
starting problem after sitting years
Recently purchased 90 ZR1 sitting for 6 years w/o starting. Changed all fluids, filters and plugs. Pumps working ,good gas and pressure at injector rails. Fuses fine.Plugs firing but no fuel in cylinder when I pulled a plug. Turns over good just will not fire on any cylinder. Drained gas had shellac smell but no gum in filter or tank. Can't imagine all injectors clogged so I wouldn't get atleast one cylinder to fire. Is there a security issue? Any suggestions on what to do next?
|
10-24-2006 | #2 | |
Join Date: Oct 2004
Location: Folsom CA
Posts: 1,655
|
Re: starting problem after sitting years
Quote:
First thing that comes to mind is VATS. If the VATS is triggered, it will kill the fuel system and the ignition. When you insert the key and turn it to start, the Security light (on the bottom left of the Tach) should flash a few times then go out. If the light stays on, then try a different key. Try locking/unlocking the drivers side door a few times with the key. Another thing that comes to mind, did the PO (previous owner) install an aftermarket alarm with an ignition cut off? These are notorious for causing problems. The ECM has a fusable link with a fuse holder. It's possible that the fuse is bad or has been removed as a security measure. It's located on a wire that comes directly from the positive side of the battery. It's a little tricky to see in there or even get your hand back there, but reach in very carefully along side the battery and feel for a small wire (10 or 12 gauge) that comes directly from the battery connector. There should be enough room on the wire to pull it out far enough to inspect the fuse. Make sure the key if off when you're messing about with this, even better if you've disconnected the negative battery cable. A spark or a short can fubar your ECM. Good luck! TomC '90ZR1 #792
__________________
TomC '90ZR1 #792 Honorary Pirate [B]If it ain't FUN, you're doing something terribly WRONG. [/B] |
|
10-24-2006 | #3 |
Join Date: Oct 2006
Location: jacksonville, florida
Posts: 43
|
Re: starting problem after sitting years
Thanks. Nothing aftermarket car only has 1100 miles will try your thoughts. Since the plugs are firing is there something that is stopping the electrical to the injectors?
|
10-24-2006 | #4 |
Join Date: Jan 2006
Location: Decatur, AL
Posts: 1,119
|
Re: starting problem after sitting years
Yes, all injectors are probably bad.
__________________
Corvette95 Registry and Forum (*************) 1989 C4 Conv Wht/Gry Auto Hardtop Top Flight SOLD 1995 C4 Coupe Purple/Blk 6 Speed 1989 C4 Conv Wht/Red Auto SOLD 1996 C4 Conv Black/Tan Auto SOLD 1994 C4 Coupe Wht/Blk SOLD 1995 C4 ZR-1 White/Gry #278 Dual Dunn Head SOLD 1986 C4 Coupe Black/Red 4+3 SOLD 1990 C4 ZR-1 Red/Red #0454 |
10-25-2006 | #5 |
Join Date: Oct 2006
Location: jacksonville, florida
Posts: 43
|
Re: starting problem after sitting years
Assumed was the problem but was hopeing for an easier fix.
|
10-25-2006 | #6 | |
Join Date: Oct 2004
Location: Folsom CA
Posts: 1,655
|
Re: starting problem after sitting years
Quote:
I have a hard time believing that ALL the primaries have failed completely. What usually happens with the '90-92 Multec fuel injectors is that ethanol in the gasoline eats through an internal seal and shorts out the coils. You can measure the resistance of the fuel injector coils quite easily without taking the plenum off, All you need is a DVM (digital volt meter)with fairly long leads. Remove the negative battery cable. Open passenger door and remove the INJ fuse, it's a yellow 20A, top row about halfway across. Remove the "A" connector on the ECM, it's the Yellow one closest to the outside drivers side. Using your DVM, measure between the correct pin on the ECM and the right hand side of the INJ fuse connector. Just stick your black probe from the DVM into the INJ fuse hole that is closest to the firewall, make sure it's got good contact. My probes were too big to fit into the pin holes yellow connector on the ECM, so I cut a 2 or 3 inch piece of solid core wire to stick into the pin hole, then I could clip the Red lead of my DVM to it. The actual ohms read from the ECM connector will vary depending on temperature and wire resistance. If you were to have measured at the fuel injector itself, the Ohms at room temperature should be 13+/-1 ohm. What you are looking for is a variance between injectors, it'll be obvious if you've got a bad one or one out of spec. No ohms at all would indicate a bad connection or a shorted coil in the injector. Low or high ohms indicate coil failure in the injector itself. Below is the appropriate page from the Helms manual that shows the primary fuel injector circuit. The dotted box at the bottom represents the ECM. The first circuit on the bottom left hand side is Cylnder 2, just to the left of the is a small Y7. This means that pin "7" on the "Y"ellow connector reads the coil on cylinder 2 fuel injector. A few of the pin numbers are on the yellow plug, they are numbered from the upper left hand side and theres 4 rows of 6 pins each. So, 7 would be second row down, first pin. Put the postive lead of your volt meter into pin 7 and the negative lead of the volt meter on the right hand side of the fuse plug for the INJ fuse. Good luck! TomC '90ZR1 #792
__________________
TomC '90ZR1 #792 Honorary Pirate [B]If it ain't FUN, you're doing something terribly WRONG. [/B] |
|
10-27-2006 | #7 |
Join Date: Dec 2003
Location: McHenry, Il.
Posts: 6,607
|
Re: starting problem after sitting years
WELCOME CARNOLD GUD LUCK.
__________________
http://i119.photobucket.com/albums/o...9mcw/SIG-2.jpg http://i119.photobucket.com/albums/o128/wb9mcw/vcm.gif "The Budget should be balanced, the Treasury should be refilled, public debt should be reduced, the arrogance of officialdom should be tempered and controlled, and the assistance to foreign lands should be curtailed, lest Rome will become bankrupt. People must again learn to work instead of living on public assistance." - Cicero, 55 BC " We the people are the rightful masters of both Congress and the courts, not to overthrow the Constitution but to overthrow the men who pervert the Constitution." - Abraham Lincoln |
Thread Tools | |
Display Modes | |
|
|