Such highs and lows....

[tonypaul]

I started up my 454 Vortec 2 days ago. It fired within 20 seconds on the first crank, no check engine light, idled and reved great. I didnt run it no more than a minute or two as I had the oil cooler lines looped together with a piece of hose and some clamps cause my oil cooler wasnt here yet. I was bouncing off the wall with excitment due to it firing right up!!!

So yesterday my oil cooler finally gets here along with a bunch other goodies. I install it yesterday afternoon a go to start it up and it just cranks and cranks.... Ahh- I forgot to put the fuel pump fuse back in. I took it out to do some wiring on my stereo. I put it the fuse in and crank it and it back fires and wont start... I crank it a few more times and samething... I pull a plug and notice its a little wet. These were the orginal plugs in the motor when I got and was planning on changing them any way. I find a parts store open today (turkeyday) get the new plugs put them in..... Same thing- no start and gives off one back fire... I start checking things, my battery cable is very very hot. I check my connections at the starter and find that the eye connector for the main power for the engine harness has lost its plastic covering and is grounded itself against the starter. I guess somehow I pulled the wires or something for it to do that... Anyway I fix the wire, adjust it so no wires can ever get ground out again... But it still wont start- still the same thing, cranks and then it back fires. My battery was kinda low around 11.1 volts so I put it on my charger. I will do a scan as soon as my battery is charged.. Can the PCM get shorted out and be ruined????
Thanks-

[67C10BUB]

Originally Posted by tonypaul

I started up my 454 Vortec 2 days ago. It fired within 20 seconds on the first crank, no check engine light, idled and reved great. I didnt run it no more than a minute or two as I had the oil cooler lines looped together with a piece of hose and some clamps cause my oil cooler wasnt here yet. I was bouncing off the wall with excitment due to it firing right up!!!

So yesterday my oil cooler finally gets here along with a bunch other goodies. I install it yesterday afternoon a go to start it up and it just cranks and cranks.... Ahh- I forgot to put the fuel pump fuse back in. I took it out to do some wiring on my stereo. I put it the fuse in and crank it and it back fires and wont start... I crank it a few more times and samething... I pull a plug and notice its a little wet. These were the orginal plugs in the motor when I got and was planning on changing them any way. I find a parts store open today (turkeyday) get the new plugs put them in..... Same thing- no start and gives off one back fire... I start checking things, my battery cable is very very hot. I check my connections at the starter and find that the eye connector for the main power for the engine harness has lost its plastic covering and is grounded itself against the starter. I guess somehow I pulled the wires or something for it to do that... Anyway I fix the wire, adjust it so no wires can ever get ground out again... But it still wont start- still the same thing, cranks and then it back fires. My battery was kinda low around 11.1 volts so I put it on my charger. I will do a scan as soon as my battery is charged.. Can the PCM get shorted out and be ruined????
Thanks-

I hate hearing stories like this. After all that hard work something just always has to go wrong. I wish I could help, but I don't know much about the Vortecs. I would think that the ECM is fuse protected. Best of luck to you. Hopefully someone with more experience with these motors will chime in.

[Super73]

Check power and ground to you cam position snesor. It will cause slow cranking and backfiring through the carb/throttle body. If you have HP tuners or EFI live, log cam pos hi and low and see if anything comes up on the scanner. If you don't see anything find out why..

[tonypaul]

Its RUNS! I charged the battery over night and hooked it up this morning. Fired right up., but it has a little pop in the exhaust like a little back fire at idle. It revs good but at idle it has a soft pop to it. I didnt run it very long as its cold here today and I only opened the garage a little. Its running a little rich also. I figure if I can get it out of the garage and let it idle for a while and let the computer pull in the timing and fuel mixture it should be fine.... Im hoping it will be fine, Im getting so close to being done with this build.Gotta do my reverse light wiring, build my rear sub box, hook up my air compressor for airbags, get the front windshield put in... OH the brakes, gotta do the brake lines... Then final buff and put on the upper and lower trim and Im done!!! Still shooting to be finished on x-mas day....

Thanks for everyones suggestions and kind words...

[67C10BUB]

Originally Posted by tonypaul

Its RUNS! I charged the battery over night and hooked it up this morning. Fired right up., but it has a little pop in the exhaust like a little back fire at idle. It revs good but at idle it has a soft pop to it. I didnt run it very long as its cold here today and I only opened the garage a little. Its running a little rich also. I figure if I can get it out of the garage and let it idle for a while and let the computer pull in the timing and fuel mixture it should be fine.... Im hoping it will be fine, Im getting so close to being done with this build.Gotta do my reverse light wiring, build my rear sub box, hook up my air compressor for airbags, get the front windshield put in... OH the brakes, gotta do the brake lines... Then final buff and put on the upper and lower trim and Im done!!! Still shooting to be finished on x-mas day....

Thanks for everyones suggestions and kind words...

Thank God. That is some good news. Hopefully I'll have the same luck after I get my injectors back from being cleaned.

[usmcchevy]

Originally Posted by 67C10BUB

Thank God. That is some good news. Hopefully I'll have the same luck after I get my injectors back from being cleaned.

Mind sharing where you sent them for cleaning?

[67C10BUB]

Originally Posted by usmcchevy

Mind sharing where you sent them for cleaning?

I sent them to Engine Performance Injectors in Whittier, CA. It was $190 OTD and they are somewhat local to me so I saved on shipping. Their phone number is (562) 693-8236 on web is fuelinjectors.com.