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High EGT's

5670 Views 49 Replies 11 Participants Last post by  smcinrox
I have an early 99 F-350. The EGT's are running higher than they used to with no modifications being done to the truck. I checked to make sure my boot connections are tight but haven't had time to do a pressure test yet. I'm going to verify the EBPV isn't stuck in a slightly closed position (hopefully tonight). If the leak test turns out good and the EBPV is not stuck closed, I was thinking about purchasing a cat delete pipe for testing to see if the cat is causing a restriction. Does anyone have a suggested place to buy a cat delete pipe? Do the experts out there think I'm on the right track? Any additional suggestions would be appreciated.
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I believe the 99's came with AB injectors. I don't know when the switch to AD's was. There was a post here in the last week or so and they mentioned the AB's flowed 120 something compared to AD's 140 something. Does Swamp recommend tuning with the larger injectors?

Have you checked the HPOP pressure? Jody told me low pressure could contribute to high tempertures. Seems counterintuitive to me but I will go with his expertise.

Mine seems to have high temps and I am trying to work one thing after another to get things right. I just got my Dieselsite pressure checker and tonight I found one leaking boot going into the intake manifold. When I get that fixed that should help some.
I agree that it probably isn't the larger injectors if they worked for 8 months. I am considering going to a larger injector someday and the AD's maybe a good choice for me. Im still learning here.

On my HPOP under full acceration it would go as low as 1400. You may need someone to watch the computer while you drive. I only saw about 1900 but I was trying to drive and watching for cops, three gauges, a speedo and the computer at the same time.

The early 99's also have a HPOP that flows less that the later versions so they don't keep up as well. Also mine has DP tuneing that causes more temp along with more power. But mine had temp problems even before. I added a larger exhaust and that dropped the temperatures some.

What kind of boost pressure can you get? I assume you still have the stock turbocharger.
You know another thing could be the gauge. I don't know how we could check it though. Maybe somebody else here has figured that one out.
I am not sure about idle but at WOT it should be above 2200 or 2400, if I remember right. Some say that 2000 is good enough. I believe the higher the better. I think the terminiator equiped ones go up to 3600 and work even better.

From what I have read the early 99's have a older style pump which isn't as good as the later pumps. Both pumps look the same outside and will fit the same.
I just ordered some from the power stroke shop. I had a leaking one in about the same place.

Part number is F81Z6C640FA for a early 99. I haven't got them yet but I am pretty sure they are the right ones. Fourty six dollars each and my dealer wanted $85 each. I probably shouldn't print that where Bob can read it.

Newer engines boots were twenty something at my dealer. Early 99 ones are more.

I got two just to be sure. I am probably going to get t bolt clamps also when I can measure them. I think the worm drive clamp ripped the boot.
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