Help Engine Light And Loss Of Power

[treefidy]

OK so this is the third time that this has happened, i was driving down the road getting ready to shift gears. in the middle of shifting the check engine light would come on and the engine would lose power? but would still keep running, it would die but still keep running!, eventually after hitting the gas several times the power would come back! and down the road i went. i stopped in at a local diesel shop "that my buddys dad owns" and told him what was happing. he said it sounded like the valve cover gasket must be going out but with out it happening there at the shop he couldnt tell me which one it is. i have never heard of this before? apparently there is a sensor of the gaskets that can go bad and cause the engine to do that. has anyone else had this problem? this concerns me. i would like some input before i dump 500 bones into these gaskets and find out that this may not be it. could it be anything else? please let me know, thanks guys

 

[treefidy]

excuse me not the check engine light the SERVICE ENGINE SOON LIGHT would come on

 

[kwazyca]

Before you spend any money get the codes scanned and see what set off your check engine light.

Or did the mechanic do this already?

I have NEVER heard of anything like this gasket thing?

I have heard of CPS failures. Injector electronics problems, Fuel feed problems , etc.

What year is your truck/motor and what have you done to it over stock?

How many miles?

When was the last time you changed the fuel filter?

Tom

 

[kwazyca]

Also,

I see you live in Reno.

Sierra Diesel on the south side of the Reno Hilton (Mill street if I remember right) used to be (95-2001) a very good diesel shop with straight shooters. Hopefully it still is.

Hope this helps,

Tom

 

[Swany]

you runnin' a chip?

 

[wftree]

If you fill out your signature it helps us answer these questions. If you have a chip or 10K or other mods it may be due to over boost. The PCM will defuel at high boost levels, I run a blow off valve to prevent this.

WFTREE

 

[wanderer]

Underneath the valve covers, is a gasket with wires, that connect to the injectors, and glow plugs. The harnesses connect to 2 injectors and 2 glow plugs. There are 2 harnesses under each valve cover. If you burn the wires on one of the harnesses, the computer will compensate, by shutting down that side of the engine, and will run on 4 cylinders on the opposite side. It's an easy job to replace the valve cover gasket, and harnesses to the injectors. Just takes time to unbolt everything. Nothing particularly technical about it, just change out the wiring.

If it was me, I would change out the CPS first. This is located on the front of the engine down low, by the crankshaft pulley. Pull the connecting harness, and a 10mm deep socket, can't remember if it requires a 12 point or 6 point. 10 minute job, and less than 100.00 for the part.

 

[Wideopen]

I agree with Wanderer ...I'd change the CPS before I got into pulling the Valve covers to search for a burnt/broken injector wire

 

[treefidy]

I have a 99 psd 7.3 cc,lb, 4by. yea sierra diesel injection is my buddies dads shop, i havent done any mods to the truck, its bare stock. 114,000 miles. no chip, nothin. i thought maybe the cps, but am just at a loss right now, i dont want to spend the money if its not the gaskets. does the cps do the same sort of thing that i mentioned??? loss of power but still running, with the service engine soon light?
Thanks guys, ill check back this aftenoon to see if you came up with anything else.

 

[jlayne]

when my harness that is in the valve cover gaskets went, it did it all of a sudden and didn't come back... it still ran with the check engine light on but missed very bad (only running on one bank) and you had to lay it on the floor board to get it up the smallest hill... it also spit out a half a dozen codes (can't remember what ones though)

i would check the CPS as well..

there is enough volts going to the injectors that most of the time when the harness short it takes out the circuit and does like mine and doesn't come back as yours did... i have also seen a few that took out the IDM (mine did) when the valve cover harness went out

that being said most people have had to replace both the cps and harness by 114k

 

[treefidy]

yea im getting concerned? i dont think that it has anything to do with the valve cover gaskets, i wonder if the waste dump is staying open? or could i have a bad code going? i also noticed that there was a unusally amout of black smoke starting to come out more, could this be a sign? it hasent poured out black smoke since the last time it happened but right up to before it happened there was a lot more black smoke coming out of the pipe. and today there wasnt hardly any smoke, could it be bad fuel, i am using a red line diesel addative but i wouldnt think that would casue it. keep in mind i have no mods, thanks guys

 

[kwazyca]

Originally posted by treefidy
yea im getting concerned? i dont think that it has anything to do with the valve cover gaskets, i wonder if the waste dump is staying open? or could i have a bad code going? i also noticed that there was a unusally amout of black smoke starting to come out more, could this be a sign? it hasent poured out black smoke since the last time it happened but right up to before it happened there was a lot more black smoke coming out of the pipe. and today there wasnt hardly any smoke, could it be bad fuel, i am using a red line diesel addative but i wouldnt think that would casue it. keep in mind i have no mods, thanks guys

What codes is the problem setting???


Autozone will loan you a scanner..... and if they can't tell you what the code means......someone here can.

Tom

 

[sagebel]

I had one of the connectors to the valve cover gasket come loose and it did what you are describing. I would also say swap the CPS.

Scott

 

[Bean]

Like others say, get the code! That will give us a direction to steer you towards instaed of shooting in the dark. Could be a # of things

CPS, TPS, ICP, IPR, MAP, or even fuel, gotta have the code # to get goin in the right direction. Pretty sure though that its not a harness problem.