jfg455

iTrader: (5)

So I swapped an LQ4 into a 92 ext cab C2500. The motor was running (I drove it into the yard) before the swap. It is an 01 LQ4 from a K2500 GMC. I swapped it into the C2500 with a 2wd 4l80 and used the stock harness modified to fit the truck. I swapped in an LS9 cam and springs, did an LS2 front cover and sensor, used a 1X cam gear, used an extension harness for the CMP sensor, swapped the A and C pins for the LS2 style CMP sensor and verified I have cam pulse in engine data, Still have the 24X crank wheel and verified CKP sensor is reading in engine data, removed VATS via hp tuners, have 55 psi fuel pressure key on and while cranking, Verified fuel in the rail s as well, have injector pulse while cranking via noid light, have spark while cranking via spark tester in line, checked all powers to PCM key on as well as cranking, both good, ECT is within 2* of ambient temp, TPS is functioning via engine data. Issue: engine cranks but does not fire. Will fire on starting fluid but then dies. Plugs are dry. The injectors and fuel rail that came on the truck were rusty and nasty. I had a clean intake, rail and injector set on the shelf from a different build with the same PN injectors so I swapped them onto the truck while the motor was out. Unknown how long they have been sitting. 2 years in my shop minimum. Could the injectors be stuck causing a no start? I could see 1 or maybe 3 but all 8? Seems odd. Thanks in advance

DietCoke

iTrader: (18)

2 years? Injectors will stick after 90 days. Bench cycle them. A good few whacks to the injector body with a wrench usually frees them up

Old Geezer

iTrader: (3)

^^^ What Coke says.
See this frequently with customer injs.....
The last set were run w/ E85, stored w/ a shot of WD in them. Still 5 of the 8 were locked up. 1 was leaking, and 1 has a messed up pattern.
I ran them for 4-10 min cycles in the ultrasonic cleaner, whacked them w/ a screw driver handle, and managed to get them all working correctly.

jfg455

iTrader: (5)

Yup, All 8 were stuck. Some tapping, manual cycling and some air pressure and they all freed up. Truck runs good now.

michaelmaxim

With your no start issue before... would the motor crank and turn over for a second then die or did it just never turn over at all?

G Atsma

You do know it's been almost 2 years since the previous post?

michaelmaxim

Isn't that what a forum is for? Otherwise threads would be locked if you weren't allowed to ask questions.

G Atsma

True, but many times the poster you are asking might be long gone. As long as you are prepared for that.....