MT 2500:) 99 5.7 cuts out only at 3000rpm

[cadillaction]

MT 2500 Where are you I've got a weird one. 99 Chevy 5.7 dually dump truck. The engine cuts out while driving at 3000rpms only. If you keep your foot in it it goes away at 3200. Does it in any gear(auto). Also, stopped and in park, it will do it at 4000rpms. Acts like a rev limiter. Fuel pressure does not change (60-62psi) when this happens, does it in open or closed loop. I disconnected the maf and no change. I've installed new cap, rotor, plugs, wires, coil, module(all original with 165K), no change. Runs sensational until 3K rpms. Any thoughts????

[777stickman]

Originally Posted by cadillaction

MT 2500 Where are you I've got a weird one. 99 Chevy 5.7 dually dump truck. The engine cuts out while driving at 3000rpms only. If you keep your foot in it it goes away at 3200. Does it in any gear(auto). Also, stopped and in park, it will do it at 4000rpms. Acts like a rev limiter. Fuel pressure does not change (60-62psi) when this happens, does it in open or closed loop. I disconnected the maf and no change. I've installed new cap, rotor, plugs, wires, coil, module(all original with 165K), no change. Runs sensational until 3K rpms. Any thoughts????

I'm sure MT-2500 will be here soon. I would suggest taking the dist cap off and checking for rotational and side to side play in the rotor. Do this very lightly while holding some light down pressure on the rotor. Keep in mind that there is no play allowed!! Some up & down play is ok.

[cadillaction]

There should be no rotational play at all??? Like the advance play you would feel in an older style distributor?

[777stickman]

Originally Posted by cadillaction

There should be no rotational play at all??? Like the advance play you would feel in an older style distributor?

That is correct. Zip, Zero, Nada & None.

[cadillaction]

I'll check that soon and get back to ya with my findings. Thanks!

[horse482]

I had a similar problem with a '97 it ended up being the coolant temp sensor. It can be checked with a scanner. If you replace it get a good one from the dealer not a cheap aftermarket one.

[cadillaction]

I haven't had a chance to work on this vehicle again yet but I'll keep that in mind. Thanks!

[cadillaction]

Originally Posted by 777stickman

That is correct. Zip, Zero, Nada & None.

Finally got around to this vehicle again. There is PLENTY of clockwise/counterclockwise play in the rotor/gear. Sounds like distributor time

[2000CAYukon]

You can replace just the drive gear since that is probably what is worn out. Much cheaper than the a new distributor.

//2000CAYukon

[cadillaction]

Originally Posted by 2000CAYukon

You can replace just the drive gear since that is probably what is worn out. Much cheaper than the a new distributor.

//2000CAYukon

Replaced the distributor...problem is still there. In park, get it up to 4000rpms and it cuts out(like a rev limiter) While driving, get to 3000 rpms and it cuts out, coughs, etc. then runs fine after 3000. New cap, rotor, wires, plugs, etc. TPS??? I've got a scanner and I believe it has freeze frame. I've just never used that feature. Any ideas?

Thank you in advance.

[cadillaction]

Also has a new fuel pump (62psi), fuel filter.. Definitely feels like it's loosing spark. New distributor came with new module, cap, rotor.

[cadillaction]

I've got an Actron CP9580 with real time data. Anything I should be looking for???

[2000CAYukon]

Have you driven it with fuel pressure gauge attached? Would be interesting to see what the pressure is doing when it cuts out at 3000 RPM. If it is electrical, it could be coil or CPS (crank position sensor).

Good Luck.

//2000CAYukon

[cadillaction]

FIXED! Crank sensor. Keep this odd one in your memory bank. Thanks to all!

[cadillaction]

Saw your post after I fixed it. Thank you though!