New to the forum. I've grabbed some info from here before. But I've run into a problem and knew this was the place to go. I've got a 350 Tpi in a truck. It was a previous owner swap. Using a painless harness. I forget the year of the motor, its written down somewhere. It has a cold start injector. I got the truck and it ran terrible. I took the intake off and the fuel rails, cleaned it all, the injectors were clogged shut almost. I put a fuel filter inline and put it back together, ran great. I did a cab swap and had to re-do a bunch of wiring. I now have the fuel pump on a toggle switch Bc the key would let it cutout sometimes. I found out the fuel pressure was 67psi, I regulated it down to 42psi. The motor has bigger injectors, 32 or 36lbs? I forget. But now it will start but won't stay running, it would start and idle for a second, rev up and die. Now it starts and dies immediately. It does not have a MAF but a MAP sensor now. New IAC, tps is working I believe. 02 sensors are older, idk how old. I had the tps set at .710? I believe is the mean for a speed density system. It seemed to be getting too much fuel, the motor stopped starting after a bit and the plugs were fouled and soaked with fuel. New plugs and it starts again. I changed the tps to .540? Just for haha's and no change, no fouling or soaked plugs though. I have unplugged the MAP, IAC, TPS individually and in pairs and it had the same symptoms. I didn't ever mess with any timing, cold start injector is still operational. I'm not sure if I forgot anything. I need to get this thing running asap to move on with this project. Its getting converted to a Carb soon if I don't figure it out. Any help would be great. Thanks

 

Well first off,I don't know how you're running a cold start injector with a speed density tpi?...and voltage to tps should be .54 volts with throttle closed and close to 5 volts at wot..check your injectors with an ohm meter..any under 10 ohms will need to be replaced.

 

This is my first Tpi engine, so I'm unfamiliar with the do's and don'ts. And like I said the previous owner did the swap not me, I was unaware you shouldn't be running a cold start injector on a Map sensor system. I have seen .54 for Maf and .71 for Map so I have tried both. I will leave it at .54 from now on. I can check the injectors.

 

Finally got a break from all the rain. I checked the injectors, they were all 14.2 to 14.4 ohms. Anyone else have anymore insight or suggestions?

 

Unless there is custom tune in the computer you have massive overfueling ;
the computer still thinks the stock 22 lb ( or even 19lb if it is off a 305 ) injectors in there and is supplying based on those

It will never run right no matter what you replace or adjust
Buy some stock size 22lb injectors ; the size you state is way too big for a 350 esp if it is stock (ish ) , guys are running 383's on 24lb injectors

 

Is it connected and functional?
Would be wired to the brass hex head switch shown next to the CTS circled below.

If not it is redundant and just plugging a hole

 

I agree the injectors are extremely large and overkill. Especially considering the use of the truck. But I have had it running and driving before. It did run well, possibly a little rich. The sensor in the front is connected to the harness. The injector/valve? On the driver side going through the hole in the intake/plenum is not wired up.

 

So it is just filling a hole

Pull the engine fault codes

https://www.thirdgen.org/forums/tech...s-dumbies.html

 

Alright. I finally got around to pulling the codes. Initially I couldn't get it to pull any codes. When I first bought the truck just the two black plugs were plugged into the computer and the yellow one was taped off. I could swear the CEL worked before. But I couldn't get it to work till I followed the wires, untaped the plug and plugged it into the computer. The codes I got were, 15 Coolant Temp Low. 22 TPS Voltage Low. 42 Electronic Spark Timing Circuit. 54 Insufficient Fuel Pump Voltage. I'm not sure about 22 and 42. I have the fuel pump wired into a toggle switch on the dash, I'm guessing this is the reason for that code. Will running it like this have any adverse affects on the system/efficiency of the motor? Also, after pulling the codes for the hell of it I tried starting it and it fired up and stayed running fine with the yellow plug connected to the computer. It did idle really high. I'm not sure where I last left the TPS set though. Didn't have time to check today. I know you're going to be shaking your heads but I know when I got the truck the yellow connector was taped off with duct tape, not connected and the truck was running and driving.