My 97 PSD has started giving me problems on cold mornings until it warms up. It starts and idles fine but if I try to raise the RPMS to 1,000 or above (in park) and hold the throttle steady it will hold the RPM's for about one seconds and then make a loud boggy sound and then the RPM's will drop to about 800 RPM or less. The engine actually sounds like it's under a load until I give it more throttle or or let up. It's a real pain to drive until it warms up. It accellerates just fine until you try to level off at a steady cruising RPM and then it looses RPM's and power until you stand on it or let off on the throttle all the while making that boggy sound. In october I changed the oil and filter, fuel filter, cleaned and oiled K&N air filter, replaced two bad glow plugs, replaced glow plug relay and did a brake job. Other than this normal maintinance the only problems I've had in the past was a cam position sensor and an alternater. Whats up now?

 

What you're experiencing is the Exhaust BackPressure Valve, or EBPV cycling. It's a butterfly valve in the housing just downstream from your turbo. It closes when it's cold enough, and increases the back pressure to help the engine warm up faster. If you'd like to, you can disconnect it. To do that, disconnect the two wire harness at the base of the turbo, in front. There's only one two wire harness there, so you don't have to worry about getting the wrong thing.
You probably won't see much difference in how long it takes for the truck to warm up, either.

 

Quadzilla
Thanks for the fast reply. I think you nailed it to because it sounds just like somebody stuffed a potatoe up the exhaust pipe.

One other question I have relating to warmups is that I seem to have more horse power during the latter stages of warmup when I floor it than when its completly warm? Not that I normally stand on it when it's still cold but once in awhile I need to floor it to get into traffic before it's completely warm and it really scoots. After its warm I feel like I'm loosing about 10 or 20 horse power? It's been running this way for a couple of years, summer or winter doesn't matter. Any ideas?

Thanks joel

 

There's a sensor in your truck called the EOT sensor, (Engine Oil Temperature). What is does is monitor the oil temp, and supplies a signal to the pcm, and the pcm adds extra fuel, similar in concept to a choke on a carbed gasser. There is a mod that fools the pcm into thinking the oil is cooler than it actually is, so the pcm will continue to add extra fuel, regardless of how warm the oil gets.

 

OK I'll bite.
Whats the mod and what kind of fuel penalty will I see?

Also I read somewhere that if you could find a Ford van in a wrecking yard, it uses a round down pipe and that it will fit in the trucks? Any truth to this or should I just buy an after market

Again thanks for the fast dead on answers. I couldn't get this kind of service if I paid for it.

Thanks
Joel

 

Its called the 10k mod. Check it out here: http://pages.prodigy.net/stevebaz/_i...az/index3.html
I did this mod about three months ago and havent experienced any fuel penalty.