Archived "Over Boosting"

[KLauber]

Today, when I walked out from school to the parking lot and got in my truck (98. 5 24 valve) and started the engine, the check engine light came on. So I take it to A. Auto and have them run a DTC code check. 5 codes came up: P1693, P0234, P0251, P0234 pending, and P0251 pending. The only code I am curious about is the P0234, which is "Engine overboost condition; turbo boost limit exceeded. " Now if anyone could please tell me if you have had the same or similar problem, and what to do, I would greatly appreciate it. (Only mods are a K&N air filter, and a MBRP straight pipe exhaust)

 

[p-Bar]

I would be concerned with : P1693 Generic fault indicating a fault in the bus or PCM/ECM interface. You may have had a hiccup in the system . Are all the codes reset now?

 

[Missouri Mule]

Since you had a code for the vp44 you mite of got an over boost condition(the vp could added fuel causing over boost) or the ECM?/PCM mite of thought there was an over boost condition because of the failure on that particular system of the vp44.

 

[KLauber]

We added a 30 AMp noise filter to the PCM to correct the trans shift hunt condition also. Would adding the straight pipe exhaust cause the overboost? No gauges on the truck. Will overboost damage the turbo and how?

 

[WDimig]

it is possible that the boost sensor is bad, and it is giving a false reading at idle, i see that happen alot on most mid range isb engines, and when that happesn the ecm defuels the truck because it is seeing a over boost condition, when in reality there is no overboost condition. some food for thought. i would try and replace the map sensor.



wes

 

[p-Bar]

I would install a boost gauge to see whats really going on. Then you can trouble shoot.

 

[KLauber]

Its weird, we cleared the codes yesterday and nothing else has popped up.

 

[Bob4x4]

I would be concerned with : P1693 Generic fault indicating a fault in the bus or PCM/ECM interface. You may have had a hiccup in the system . Are all the codes reset now?

:-laf Once again 1693 is not anything more than telling you to look for a code in the other module



Bob

 

[p-Bar]

:-laf Once again 1693 is not anything more than telling you to look for a code in the other module



Bob

Glad we have the PRO online to help out. Going to SEMA?

 

[Bob4x4]

Probably not... ... ... ..... too busy

 

[KLauber]

The check engine light popped up again! Hey Bob4x4, What would you say about the other codes? What should we do? The shop is saying that we need a new injection pump, which i think is crazy b/c the vp44 in my truck has been rebuilt. Also, could it be the lift pump failing?

 

[p-Bar]

A good shop can plug in a test system to confirm the VP is bad. Put a pressure gauge on the fuel pump your truck should not be with out one

 

[KLauber]

What exactly does the test sytem tell the mechanic if the VP44 is dying? If the lift pump is running less than 5 psi than will the VP 44 throw a code? Which one?

 

[Bob4x4]

What exactly does the test sytem tell the mechanic if the VP44 is dying? If the lift pump is running less than 5 psi than will the VP 44 throw a code? Which one?

P0216

Fuel Injection Pump Timing Failure



The injection pump must have suficient fuel supply to be able to control fuel timing(and to survive)

 

[KLauber]

We saw P0251. Is that similar?

 

[Bob4x4]

We saw P0251. Is that similar?

P0251

Fuel Injection Pump Mechanical Failure Fuel Valve Feedback Circuit



Internal injection pump code... ... ... ... .....

 

[KLauber]

P0251

Fuel Injection Pump Mechanical Failure Fuel Valve Feedback Circuit



Internal injection pump code... ... ... ... .....

So we'll save our money for a new/rebuilt pump and continue driving until it fails. My son only drives around town anyway.....

 

[JayStraight]

Did you ever find a good trans shop in the Upstate????



I've used Advance Transmission in Mauldin before on an E4OD and they were great to work with... ... just a thought.



-Jay-