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Limp mode LLY bone stock help!!!!

6600 Views 11 Replies 5 Participants Last post by  ALLY Cat
My wife just brought my truck home in limp mode. CEL is on and is throwing 3 codes - P0089, P0090, P0404. Truck is bone stock, just replaced fuel filter 800 miles ago. there is also a knocking sound at idle, im guessing fuel knock. throttle hasnt been as responsive as it was when i puchased it a year ago either. Also, the exhaust smells funny, smells like an additive, but there is no additive in the tank. Any help would be awesome. Thanks. :help
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Few suggestions for the P0089 and P0090:
1) Check your FPRV with the bottle test
2) Check for bent/damaged fuel lines
3) Verify you have prime at the fuel filter head (open bleed screw and check for bubbles)
4) Check demand vs actual fuel rail pressure

Most common fixes for this seem to be change the fuel filter first (which you did) and otherwise replace the FPRV and fuel pressure sensor.

The P0404 may be a clogged EGR system, but I would just solve that one with an EGR blocker plate and a "fingerstick".
Now I have 3 more codes, p0299, p0403, and p1093. Could a bad cp3 or fpr cause all these codes or is everything failing in my truck at the same time?

Ok, here's your latest set of codes:

Code: P0299
Description: Turbo Underboost

Code: P0403
Description: EGR Circuit Malfunction

Code: P1093
Description: Fuel Rail Pressure Low During Power Enrichment

It still seems like the codes are centering around your EGR and the fuel system. I doubt it's a bad CP3 or FPR, but I do think you may have an issue with fuel not getting to the CP3. Again double check all the engine bay wiring harneses for chaffing and rubbing and ensure all your grounds are good. I'd pull off the fuel filter again and just verify everything was done well and you don't have any air leaks at the WIF, filter head or bleeder screw. You can also pressurize your gas tank (5-10 psi max and leave it pressurized for at least 1 hour) and see if you have any leaks in the fuel lines leading going from the tank all the way to the CP3. I already mentioned how to tackle the EGR issue above. In order to monitor any of the other electronics and sensors beyond that, you're either going to need some sort of unit like an Edge Insight or bring it to the dealer.
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