Engine/Transmission (1998.5 - 2002) Help Please!

[hoverlover]

Since it's gotten colder around here (in the single digit range), I've been having problems with my truck after I first start it. It starts right up, then it runs real ruff and smokes like crazy until it warms up. Also when I put it in gear the tach will drop to almost 500 rpm and the motor sounds like it's going to die, but then it comes back to normal. My fuel pressure is 20psi @ idle, also I cleaned my IAT about 2000 miles ago. The truck only has 32,000 on it and there are no codes set. Could it be my VP-44 causing the problem and if so is there a way I can test it? Any help would be greatly appreciated. Oh and by the way after it warms up to about 160 on the thermostat everything is fine. Thanks!

 

[LSMITH]

Have you ever adjusted the valves? Stock injectors?



Your fuel pressure is just a tad high, but should not cause what you are having. A tighter TC will do what you describe on the RPM when the engine is very cold, I would not worry about that at all.



I assume the smoke when cold is blueish grey? Sounds almost like you have one grid heater element not working. Does the ammeter drop down to about 8 or 9 volts and stay there on a cold start?



FWIW, my truck does the same thing, and always has. The big difference is my truck smooths right out as soon as it has run for 10-15 seconds and the grid heaters are going good. My truck does smoke pretty heavily until warm though, but the smoke stops well before the needle moves on the water temp gauge.



If in sub zero weather my truck will run rough and smoke out an entire parking lot for nearly a minute if I do not bring the idle up to about 1000 rpm. With the higher idle it just smokes out the lot while running smoothly .

 

[pwr2tow]

I have a tighter TC and have never experienced your problem.

On a electronically controled engine a Tight TC should not make the engine run rough, the electronics keep it from doing that. On a mechanically controled truck it will do what your discribeing, so since your truck is an electronic controled engine you could rule out the TC.



I don't know what your truck problems are but I wanted people to know about the TC part that LSMITH was talking about.



Ron

 

[LSMITH]

Ron, I simply meant that when the engine is stone cold and you are running a tighter TC the RPM WILL drop a little until the ECM catches it and brings the RPM back up. Even when fully warm it will drop a tad before the electronics catch it. I never said anything about the TC making it rough, but if it is running rough a tight TC will accentuate it.

 

[Joseph Donnelly]

I agree that you should check both grid heater elements to see they are working right, and continue working until 20 mph (at least if the 99 is the same as the 97). Put a winter front, even a large piece of cardboard, in front of about 3/4 of the radiator for in-town and start-up.

 

[pwr2tow]

LSMITH,

I guess I read your post differently than the way you described it in your recent post, another good reason to clear things up when in question.



You and I are both right, the TC will not cause the problem just accentuate it.



hoverlover,

On start up smoke is natural and the colder the more smoke there will be. If you have larger injectors the more chances there will be even more smoke and rougher idle, I have heard of some people haveing real problems with rough idle and big injectors at low temperatures and then again some have no problems, go figure ha, I'am not saying this is your problem but it is something to look into.



Ron

 

[hoverlover]

Thank's for the quick replies. In response to if I have adjusted my valve's I have not. I understand that I don't need to do that until 150,000. My injectors are stock. And for the grid heater my ammeter only goes down to the first white line never to 8amps. Is there a way I can check my grid heaters?



Thanks

 

[work2muchplay2little]

You might try plugging in the block heater - you'll have heat quicker and a lot less smoke. To check them, you could try disconnecting one and then the other and see if you get the same voltage drop - you could also put an ohm meter on them and check the resistance - I think most of the time one of the solenoids mounted on the inner fender well goes bad instead of the grid itself.

 

[hoverlover]

Maybe I misled you guys somewhere, I'm not that concerned with the smoke, more so with the roughness of the engine and the loss of rpm when I shift into gear. The truck sounds like it's going to die. Also if I press the go pedal the RPM drops again to about 500 RPM. Does anyone know what resistance I should see on the grid heaters and where I can test them. I have owned the truck since new, but this is my first winter with the mod's so I'm a little in the dark as to whats normal and whats not. The truck is a whole different animal!



Thanks Again!