OK, here's the deal... I did a TBI to TPI swap in my Yukon and I'm having some MAJOR issues....

The engine starts up then dies approx 2 seconds later....

The engine ran perfectly with the original 92 TPI setup, but never again after I swapped in a Holly Stealth Ram intake....

Here are some area's I've already checkes and worked on. Got a brand new in-tank 255lph fuel pump, pressures good and holds just fine to the rails. When the engine dies, pressure doesnt drop, so I think it's safe to say the fuel pump and fuel delivery is good....

All the senors are new, so is the harness. Spark is there (as the engine does fire up). I tested the coil and it checks out. The computer is the 730 unit and the VATS has been removed from the chip / ecu.

I cant find any vac leaks or loose connections. Everything seems to be tight and on. The spark plugs as well as the wires, cap and rotor are new.

No trouble codes are stored, just get the normal code 12....

TPS is set and working. All 8 fuel injectors are new and have been tested.

This problem is really annoying the hell out of me! One thing that I should note, the 730 ECU I'm using was sitting in my shop for 5 years, could they go bad? I don't think they could, but just wondering? Another area or I should say unit that has me thinking is the Ignition Module in the distr. If that went bad, would the engine even start? The oil pressure switch has also got me thinking, but it's new. Could it be bad too? The engine does the same thing with the Oil Pressire switch connected or not. Starts, runs for a whole 2 seconds, and then dies.

Also if you try and gas the engine up durring those short two seconds, the engine shuts down. If you give a little gas durring the start up, the engine revs up and then does out again like clock work.

The TPi setup is from Street & Perrformance and is said to be stand alone setup. Simply provide fuel and 12volts and turn the key, but that's not working for me.

The Holley intake does not have and support an EGR valve, would that cause such a problem? The heads have a port there, but with the Holley it's not used, would do this?

Any ideas, advice, input or suggestions? Anyone have similar or same dilema and had it fixed? Thanks a million guys!!!!

 

i would try the oil pressure switch and the ignition module first, to start cheap and easy

then it could be the ecm

 

Just ordered a new oil pressure switch, new billet distr with ignition module, and a used 730 ECU. I should have everything in by the end of this week and I'll give it a shot. Keeping my fingers crossed!!!

 

sounds good, keep us posted

 

OK Here it goes....

Don't really know why this was the case, but I decided to swap in the original TPI setup I had on my 383 and yank the stealthram off, and wa-la, the bad boy started right up! I don't know what was up with the stealthram setup, but something - I think in the fuel delivery was off or not working properly (adj fuel press reg maybe?). Anyhow, I'm going to run some tests and see exactly what was up....

A HUGE thanks to BRAIN at TPICHIPS.COM / TBICHIPS.COM for ALL his help! If you need a custom chip, he's your man!