I have searched, read, and pulled my hair. I am so fed up I can't stand it. I recently installed a 350tpi motor in my 1991. I have attempted to start it. After finding the starter enable relay screwing up, when I try to crank it, I have to mash the pedal in order for it to fire up. Then I have to hold it for it to continue to run like dirt. When I release the pedal it cuts off. By idling it up to keep it running I tried to check the timing with the est in bypass. The timing marks are not even visible. My timing light has the dial on back. I can't even bring the mark up. I have checked to make sure the distributor is installed correctly 4x. I have installed a new tpi fuel pump.
And to top everything off, I tried to check to see if any codes. I jump out the aldl port, but when I turn the key on the engine light blinks once and then stays on. Could all my problems be ground related?

I really could use some help.

 

So, you installed a 350 TPI to replace your 305 TPI?

Fuel pressure good? Injectors good? All vacuum lines hooked up correctly and/or not leaking?

 

no originally it was a 305tbi.

 

If you are running the TBI fuel pump, you're not pushing enough pressure to run the TPI set up. TBI runs around 14-18 PSI and TPI runs 40PSI or so. You'll need a new pump, new high-pressure fuel fittings (if you're currently running clamped fittings) and I'd get a regulator to make sure you're runnign the right pressure. Check the TPI forums here for most of this, should point you in a good direction. Also, the engine swap forums should have some of the info that you're looking for.

 

Also, If you haven't swapped over to a TPI ECM, you'll need to do that because the TPI set up won't know what to do with your new set up. It'll be all confused.

 

ok, I failed to mention. I got a complete motor w/computer. I installed a TPI fuel pump. The computer has a hypertech chip in it. also had the tpi wiring harness.

 

So did you re-use the tbi harness for your tpi system? or did you change the entire harness to tpi?

 

I changed out the entire harness. I have done some reading on here about the ohming out the injectors. I am going to try that next.

 

First of all before you check the timing , you need to get it running right or idling correctly. You may have one or more bad fuel injectors too. You should be able to insert a paperclip into A and B on your aldl terminal and retrieve codes. If not check your engine grounds behind your heads. Then post back.

 

So it is a tpi harness? What year car? what ecm and prom did you use? what size injectors? what knock sensor? need more info to be precise.

 

Yeah, assume we're all idiots when posting what you've done, tha'ts the best way to make sure we don't make any asssumptions about what you've done or haven't done.

 

http://www.youtube.com/watch?v=_g8PdrT0MCU

that should help with the fuel injectors

 

I used the tpi harness, the computer, knock sensor, everything that was originally on the tpi motor. All I done was take everything pertaining to the tbi out and put in all that was tpi. I have a 1991 RS. The donor car was a 1990 IROC.

 

Ok, then. First, have you tried to get it running by turning the distributor while someone is cranking it for you? If that doesn't work and you are positive that everything is connected like it should be then i would look toward a possible bad ecm or more than likely bad injectors. Now you should be able to pull codes if the ecm is good. Verify all of your engine grounds like i said earlier too. Do you know if your fuel pump is actually coming on? Did you connect the knock sensor to the correct blue wire under the hood? You should also verify that the prom is for the correct engine. Basically ,ohm out you injectors first and verify your engine grounds, and get that thing pulling codes!

 

thanks. I know the fuel pump is coming on because I can get it to start. It starts the cuts off. I can keep it running (rough) by holding the pedal. I am going to recheck the engine grounds are connected and ohm out the injectors. I hate to think of a bad ecm. I have always worked with old style motors. I am really discourged. If it is not one thing it is ten others. again thanks for your input. I will check the grounds and injectors. I will also go to Advance Auto to see if I can get a fuel gauge to check pressure.

 

Probably not bad injectors or fuel pump.

More likely, the plug wires are one position out, and consequently the spark goes to the wrong cyl when you try to set the timing right.

Try moving them all one spot clockwise around the cap, and rotating the dist housing about 15° CCW in the block. It'll either work, or ... not. If it doesn't, try moving them one spot counter-clockwise from where they started. It'll either work, or ... not. If "not" in both cases, come back and we'll try again.

 

ok, I went to Autozone and got a fuel pressure tester on loan (not cheap-$160). Today I checked the pressure. It was reading 45 to 48.So I moved on. I found 1 ground that hadn't got connected. I moved the plug wires one space and worse. I went the opposite way and a little better. When I was moving the wires I noticed the plug wires at the distributor were rusty. Initally I ohmed them out before installing them and they checked great. Well anyway, I replaced them with the ones off my tbi motor. Turned the distributor a little and she fired. I was able to set at 6 for right now. It still seemed to surge a little, but when I connected the bypass it straighten up. I cut off. The only thing is I still can't the aldl to give any codes. It just stays solid. I disconnected the battery and reconnected it. Now when I fire the engine the light is not one for the moment. I figured this was a good place to stop. Thanks for all your help.

 

One more thing though. On the wiring harness where the it starts to go into the fender well on the passenger side, there a small gauge ORANGE wire coming out of the harness. It is in plastic wire loom. Where does this go?

 

I am going to wear out my fingers typing. I forgot also to mention, that my oil pressure gauge is not working. I changed with the one from my tbi just for grins and the same thing. I put a mechanical gauge on it to make sure I had pressure and had about 50psi.

 

That wire goes to the battery... it's the ECM power.

That would explain why it doesn't run right.