Alright, if I plug the block heater in the truck fires up and is good to go, even in the colder winter weather. Now with nights only getting down into the 50's without the block heater plugged in it starts but you can tell a cylinder isn't firing. (Auto starter is on a 30 sec delay for glow plug warm up) If you start to drive down the road and give it a little throttle the cylinder will kick in and be good to go. I replaced the glow plugs about 5 yrs ago and with that also a undercover harness on the driver side. I know my injectors have a lot of miles on them 261,000 and I am guessing from the injector kicking in with throttle application that it is an injector problem and not a wiring problem? Do you guys think I am on the right track with that? I know I need a set of injectors I am just still not recovered from doing all the top end work last month.

 

Sounds like a worn poppet valve seat causing low clearance between the armature plate and poppet body. The oil trapped between them causes a suction and as the injector warms up, the suction is easier to break so the injector starts to operate.

 

You could have what happened to me ? Replaced drivers UCVH all was good till next year and then the pass side took a dump!

Smokie

 

You could try Tugly's method and point an infrared thermometer at the exhaust manifold and see which cylinder is still cold when you first fire her up. Ohm, out the 42 pin connector to see if there is a wiring problem, then do Pika's check by looking under the valve covers when you start it cold and see if there is oil coming out of the spouts. If any of these show you anything, then you have a direction to go in. 261,000 is 100,000 more than I got out of mine.

 

All very good things to check. I have never ran the truck without the valve covers on so I am going to have to do some research as to what to look for. The infared thermometer is also a good idea. Will have to try that also.

I know I have gotten way past the life of the injectors. That bill is a tough one to swallow though.

 

I hear you on the bill. The valve covers is intimidating at first, but not terrible. You just have to make sure there is nothing that can get sucked into your turbo, no loose rags, plastic bags, etc. Take a bungee cord and attach it to the hood and hang the 42 pin connector up out of the way of the rocker arms. It will not make a mess.

 

Okay. Thx. I was hoping to squeeze a little more life out of these injectors. I may be trying to squeeze to hard I guess.

 

The only time I ever had a mess from it was when it was about 15 degrees overnight and I pulled the valve covers and started it. The oil was too thick for the return passages and it overflowed at the back corner of the head. I just shut it off, let it drain and restarted it. Did that a few times until the oil thinned out enough to flow back without overflowing.

 

I think the stick jockey nailed it.
Time for injectors.

A sure fire test for poppet valve wear is by measuring between the armature plate, and injector body with a set of feeler gauges.

On a healthy injector you want to see a good .003-.004 clearance.
At .002 they start getting noisy... at less than .002 they start sticking.

 

Boy, do they ever. I've got a couple right now that that are less than .0015 and won't fire until EOT gets up close to 100F. It's really getting close to time to pull them and deal with it, I guess.

 

Anybody have a pic as to wear I am measuring.

 

Once you have the injector(s) narrowed down, remove the solenoid from the top of it. There's a spacer under the solenoid that surrounds the square armature plate that has the screw in the middle of it. Remove the spacer as well. You may have to slide the spacer a little to break the oil suction holding it in place after you remove the solenoid. Then use feeler gauges to see which is the largest you can slide under the armature plate, between it and the poppet body, all the way around.

 

That is clear as mud...........no seriously thank you. I will look into this. Will be a week or so. Leaving for Jamacia tomorrow morning.

 

Seth... if you don't have an infrared thermometer, poking a long dinner candle at various sections of the exhaust manifold through the wheel well at cold start might offer a clue too. I'd hate to pull VC's unless I had whatever new parts I needed in hand so I could install them without pulling VC's twice. I'm not in the 45 minute club.

 

That's for both of them now... I can suggest the tools to make it quicker.

I haven't been ignoring you Seth, everybody has this covered.