OK i figured out how to check my computer codes. The ones listed in the title are the ones that were stored.

The Problem i was having with the truck is that it would run fine one minute, then randomly go crazy, idle up down, and sometimes stall out. There was no fixed interval on this. It would run fine, do this, then go back to running fine.

After reading that 33 Was Map sensor i replaced it. First off do i need to reset the computer so that it knows a good sensor is in place to make corrections?(i ask because my honda has to do this)


i was hoping that this was my issue and that it was in some way causing 44 and 45.

After replacing it which i did at autozone, it drove fine and i thought i had done it. I did not =/

Would a bad O2 sensor cause the issue i described? Also the computer is still flashing the MAP sensor code.

Thanks in advance.


24 Vehicle speed sensor A fault in this circuit should be indicated only when the vehicle is in motion. Disregard Code 24 if it is set when the drive wheels are not turning. Check the connections at the ECM. Check the TPS setting.

33 MAP sensor Check the vacuum hose from the MAP sensor. Check the electrical connections at the ECM. Replace the MAP sensor. *

44 O2 sensor indicates lean Check the ECM wiring connections, particularly terminals 15 and 8. Exhaust. Check for vacuum leakage at the TBI base gasket, vacuum hoese or the intake manifold gasket. Replace the oxygen sensor. *
45 O2 sensor indicates rich Check the evaporative charcoal canister and its components for the exhaust presence of fuel. Replace the oxygen sensor.

 

You nust clear the codes by pulling the ECM B fuse for about 1 min or the cide is forever logged. Reset the codes and wait for the check engine light again. The o2 doesnt play a huge role in the engine running, i would view those codes as result of another problem. If i had to take a guess i would test the TPS, MAP, and vacuum pressure.

 

Ok i reset the computer. Im still getting code 33 (MAP) but all others have gone away. I am at a loss here

 

Here is a vid of what my truck is doing

 

find a vacuum gauge and see how much vacuum your engine is producing. If you engine vacuum is low it can throw a map code. If engine vacuum is good try testing the map. This site has good info, you need a multimeter Part 1 -MAP Sensor Test (P0106, P0107, P0108) (GM 4.3L, 5.0L, 5.7L)

 

another thing ive noticed is that during the time its doing its bad stuff the check engine light come on. Once its goes back to normal the light goes back off.

Also, as far as the vacuum, if it were low wouldn't it always be low and not randomly low?

 

I'd say yes, but i've seen stranger things happen. But it can compensate for a low vacuum situation for a while, then not be able to under certain conditions. Test the map sensor and the voltage to it and the ground path for it. Still a vacuum test would help rule things out.

 

I'd also suggest to check wiring and connectors for corrosion and continuity. Had that problem on a 1994 S10 and finally found out that it was one of the connectors behind the air filter on the firewall.

 

popped the vaccum hose off my egr and it ran fine. Capped the egr for now until i get a new one

 

Take off the egr and clean that bugger out. New ones are 200 smackeroos. Just take it off and clean the carbon out of it and the hole on the intake that it covers. Egrs just not closing off properly cause some gunk is jamming it. Ill eat my foot if im wrong... You can also return that map sensor and get your money back. Use it to buy some pipe cleaners, combustion chamber cleaner, and an egr gasket with a screen, and some beer to drink while you use those other things the clean it out. You're welcome. And next time you decide to throw parts at your truck instead of consulting us enthusiasts first, we will smack ya.