Engine/Transmission (1998.5 - 2002) Boost values

[hsmith]

Trying to help a friend with this one over the phone. He has a transmission shop and is trying to solve a driveability problem with a '99. He is telling me his scan tool is reading boost pressures. My question is, does the ECM/PCM monitor boost on the early 24 valves?

I'm thinking he is getting some false readings, as we do some time. Anyone have any ideas?

Thanks

 

[hsmith]

After my first post, got to thinking, not always a good thing, but maybe he is reading MAP values and his scanner is showing it as boost.

 

[sslechta]

I'm fairly certain the answer is 'yes'. I have a '99 and my mechanic was troubleshooting a sporadic low power condition and he plugged in his scan tool and we found that the computer was indicating 0 boost when my gauge was indicating a couple of pounds. We replaced a bad boost sensor and the problem was fixed. Bottom line according to him, when the bad boost sensor was telling the computer that there was no boost, the computer was defueling, causing low power (a mild understatement I might add!).

 

[hsmith]

OK, now I have this truck, and it does monitor the boost. It does have a turbo boost sensor, but is more commonly known as the MAP. It is definitely giving false values causing the driveability problems. Will replace it tomorrow.