INJECTORS Always Powered UP

MurphyIsmyName · #1 03-06-2006, 08:36 AM

I thought I had a fuel problem, but now my injectors are receiving 48 lbs of pressure at the shratter valve. I am getting fire and it fires up when you use an outside source sprayed into the intake. It acts like it wants to start but it won't. I checked the fuel injectors and they are all showing 12 olms of resistance. I checked the power going to the injectors... When the ignition is turned off it is showing a positive ground. I dont know if that is normal. WHen the key is turned on the ground is gone... and it shows 12 volts... all the time. When cranking it when not cranking it what ever... always 12 volts. No pulsating what so ever. I was hoping one of you has heard of this problem before. If it isnt to complicated to fix I would much rather fix it than got o carb... but I have to have it running either way by the end of this week. If I go to carb will the distributer and ignition system still work? I have an 87 Iroc for parts that is carb that I will use as a donor car, so what ever I need I am sure I will have... but Like I said, I would much rather keep it tuned port if possible. ANY info anyone knows would be extremely helpful.

Thanks....

maxwedge · #2 03-06-2006, 08:55 AM

Scan it and see if you have cranking rpms if not the crank sensor could be bad.

MurphyIsmyName · #3 03-06-2006, 07:00 PM

When the engine is cranking the tach goes over beyond the red line. When I put the key in to get the computer to flash codes... the only code I get is 22... Low voltage at the TPS. I wont be able to actually put it on a real scanner til tomorrow evening. The check engine light is on though if that makes a difference.

malletslinger · #4 03-06-2006, 08:02 PM

Have you check all the wiring in the engine compartment for cuts, or melted spots?
Have you checked your fuses?
If you dont find any wiring issues or bad fuses, then I guess you need a new TPS...

Morley · #5 03-07-2006, 03:33 AM

What you are seeing for power is NORMAL. With the key on there will be 12v on BOTH injector wires (when checked to ground). The way the ECM operates the injectors is to provide a ground on one of the wires when it wants them to fire. Go to your local parts store and tell them you want a "noid light". This plugs into the harness in place of one of the injectors. While you watch the noid light, have someone crank the engine over. If the light flashes, the ECM is firing the injectors, check each injector position. If the light isn't flashing in any position, then the ECM isn't seeing the refrence pulse from the ignition module. This is either a bad module, bad wiring from the module to the ECM, or a bad ECM. The module is usually what has gone bad.

MurphyIsmyName · #6 03-07-2006, 10:49 PM

Well, I scanned my car today, and according to the scanner the computer is not putting out any information. I followed the technical manual and checked the circuits going to the computer plug and to the computer and from what the book is telling me either the computer or the Chip inside is bad. The computer was replaced but the chip inside was not. My uncle has an 88 Iroc tuned port computer and I am wondering if it will work on my car good enough to see if it will run. I know the numbers may not match up exactly, but it has the same engine and also as tuned port as well.

Morley · #7 03-07-2006, 10:54 PM

Quote:

Originally Posted by MurphyIsmyName

My uncle has an 88 Iroc tuned port computer and I am wondering if it will work on my car good enough to see if it will run.

If you have a 1986-1988 TPI engine (305 0r 350) the memcal from his IROC will allow it to start and run. If you have an 89, you will be S.O.L. because your car will have VATS. If you have a 1990-92, forget it, different ECM all together.

malletslinger · #8 03-07-2006, 11:11 PM

What year is your camaro Murphy?

malletslinger · #9 03-07-2006, 11:20 PM

Quote:

Originally Posted by MurphyIsmyName

Well, I scanned my car today, and according to the scanner the computer is not putting out any information.

Do you mean you are not getting the code 12?

Quote:

Originally Posted by MurphyIsmyName

The computer was replaced but the chip inside was not.

You did transfer the chips from the old computer to the new one, right? How old is this new one?

malletslinger · #10 03-07-2006, 11:30 PM

Quote:

Originally Posted by Morley

If you have a 1986-1988 TPI engine (305 0r 350) the memcal from his IROC will allow it to start and run. If you have an 89, you will be S.O.L. because your car will have VATS.

Are you shure about that Morley?
Back when I was having electrical trouble(not too long ago

) I got a spare ECM(incase I fried mine) off ebay for my 89...it was either out of an 86 or an 87...It came with the chips in it(I looked), I took mine out and plugged that one in...and it worked fine, no difference at all...
I didnt think the vats was tied into anything but the starting system...

My camaro is the MPFI V6 incase that makes a difference.

Morley · #11 03-08-2006, 12:15 AM

Quote:

Originally Posted by malletslinger

Are you shure about that Morley?
Back when I was having electrical trouble(not too long ago

) I got a spare ECM(incase I fried mine) off ebay for my 89...it was either out of an 86 or an 87...It came with the chips in it(I looked), I took mine out and plugged that one in...and it worked fine, no difference at all...
I didnt think the vats was tied into anything but the starting system...

My camaro is the MPFI V6 incase that makes a difference.

1986-89 TPI's all used the 165 ECM, he can use any of those ECM's but he wants to use the memcal (calpack, prom, etc). The 86-88's all used the coldstart injector, the 89 did not AND in 89 they started using VATS on the F bodies, So if he used an 89 memcal he would have to have a way to bypass vats in the programming and the 89 has an enrichment routine in the prom for cold starting. So, with a cold start valve AND the enrichment routines he would flood the engine trying to start it, unless he unplugged the cold start valve, but that still leaves VATS.
The simplest thing to do is try a memcal from an 86-88 TPI, be it firebird or camaro.

malletslinger · #12 03-08-2006, 01:42 AM

But I didnt switch the chips...I used the ECM just as it came, and my MPFI didnt have any issues with it at all. If what you are saying is true, then why didnt I have any issues??? Im not trying to prove you wrong or pick a fight.... you obviously know this stuff and I am genuinely curious.

Morley · #13 03-08-2006, 02:05 AM

Quote:

Originally Posted by malletslinger

But I didnt switch the chips...I used the ECM just as it came, and my MPFI didnt have any issues with it at all. If what you are saying is true, then why didnt I have any issues??? Im not trying to prove you wrong or pick a fight.... you obviously know this stuff and I am genuinely curious.

Does you car have VATS? If it does, then using a memcal from a non VATS year would prevent the starter from engaging.
Even in the V8's there were not enough differences in the programming to prevent a car from running, VATS is about the only one.

malletslinger · #14 03-08-2006, 02:33 AM

Well my 89 does have VATS, and the memcal was from a non VATS year...but my car started right up... If what you say is true, then how could this be possible?

Morley · #15 03-08-2006, 12:26 PM

Quote:

Originally Posted by malletslinger

Well my 89 does have VATS, and the memcal was from a non VATS year...but my car started right up... If what you say is true, then how could this be possible?

Your previous owner must have bypassed the VATS. what's harder is putting a VATS enabled prom in a non VATS car, causes all kinds of problems.

POST REPLY TO THIS THREAD