nidfd112

Had a truck come in with one of number one cylinder exhaust valves was burnt on it. Customer wanted to replace cylinder head and we did. Finished the installation and when we started truck up it runs for 15-20 seconds fine and after turbo spools up it develops a knock in the engine. If we cut number one injector out with computer knocks seems to dissappear. We have removed pan and inspected cylinder wall, piston and bearings and also have changed out #1 injector. Does anyone have any ideas on what to check out next.

Have an MP7 in a GU713 mixer that has a stutter at around 1400 RPM's as you hit a hill. You will drive along and all of a sudden it is like you threw an anchor out and starts to bog. If you accelerate hard you can hear the turbo spool and it will eventually come out of it. Drove it today with cruise set at 1400 RPM's and in 6th gear and it would do it all the way up the hill. When we got back to shop idled truck up to 1200 and it just surges about 200 Rpm's. Nothing comes up on computer when its doing it and no stored or active codes. Did a cutout test on injectors while it was parked and engine quits surging until turning injector back on. Anyone have any ideas where I should start.

I am not certain but I thought customer had put injectors in awhile back but I will check.

Truck has 389,000 miles on it and he only uses it to haul corn to the elevator. Where we live there is no big hills such as mountains. Longest hill around might be 1/8 mile and it does it on that. Not all the time but when we test drove it this morning we had to drive about 30 minutes before it acted up. If you even touch accelerator it won't do it. The owner did say that on occasion when he shifted he noticed that the tach would jump up. Otherwise truck runs absolutely perfect. Hate new technology more than anything.

I got a 2006 CXN613 with a Mack engine and if I go down a hill and don't touch the accelerator I get a miss at the bottom. Will usually go away in around 2-3 miles. If I touch accelerator at all it won't miss. No check engine light comes on and brought to the shop and they said it had two stored faults for turbo actuator that were old and didn't think it was them. Drove truck a week and then went back to shop and no new faults showed up. Anyone have any suggestions.

I have a 1994 CH 613 with V-Mack1 and I am getting an occasional 3-3 code. Checked wiring and connections and all seem fine. Only getting code at higher RPM's. Followed the steps for troubleshooting and all is stating that it is good. Light is only on while engine is running and for a short time usually. Could get the light to come on if you set throttle at 1000 RPM's. Have another truck here with a good FIC module in it and stole that one and plugged it in and now my light only comes on very sporatic. But it still comes on and its still a 3-3 code. Anybody have any ideas that could help me out.