seawolf06

16 - Low resolution pulse not found

I hope this does not mean that my nearly brand new MSD optispark has crapped out already. It was driving perfectly with the exception of the MAP sensor code and then it started surging at part throttle. (<20% TPP) This is not cam surge as it wasn't doing it before the codes.

51 - EEPROM program error

I think this one and the 16 above might be related as they occurred at the same time. Not sure which is causing the surging, though.

64 - Bank 2 (right) O2 sensor, lean

Also just happened today, but before the two above. I thought it might be because the header bolts need to be tightened up. I couldn't reach the back few because it was so hot, but the front few were pretty tight. I just installed an aluminum elbow yesterday. Could this be caused my the valve adjustment being slightly off? They're not making clacking noises or anything.

33 - MAP sensor, signal voltage high, low vacuum

Could it have caused 64? It's been on there a couple days, but I haven't had a chance to test on it yet and it didn't change drivability. The sensor seems to be working as it gets up to the BAR reading at WOT and runs from 10-20 at cruise and idle.

Any ideas or experiences you have would help me out greatly. Thanks.

Guest47904

Reset all codes. If the 51 comes back. Have a company like Auto Value reprogram the PCM. They are all over BR. Ours here will refund the programming charge if you have to purchase a new PCM. If you get a 51 again, time for a new PCM.

Injuneer

First, check the grounds, particularly for the PCM. Multiple codes can often be traced to a bad ground

16 - Low resolution pulse not found

Check the harness connectors - one at the Opti, the other the gray one on the bracket on the passenger side of the intake manifold - look for corrosion of bent/broken pins. This will often show up as a "stored" code, set on startup when the PCM has a brief problem locating the pulse signal. As noted in the post above, clear it and see how long it takes to come back. If it was an "active" code, the engine would not be running, since the PCM would shut down the fuel system.

51 - EEPROM program error

Check the grounds.


64 - Bank 2 (right) O2 sensor, lean

Put the scanner on it and look at the long term fuel corrections for BOTH banks of the engine. See if the left side, or both sides are indicating BLM's approaching 160. That will tell you if the problem is on one side or both sides. For the code to set, the right O2 sensor would have to indicate less than 200mV for 50 seconds.

33 - MAP sensor, signal voltage high, low vacuum

Check the harness connector for the MAP sensor. They seem to crumble from the heat, and give intermittent readings. If the +5V reference voltage from the gray wire was bleeding through to the light green wire, it would set this code. The code sets when the TPS is less than 4% and the MAP reading exceeds 68kPa for 5 seconds. A big cam or rough idle/misfires can cause this problem. A very low voltage/high vacuum can cause DTC 64, since the PCM thinks the engine is not under load, but you have the oppostie situation.

seawolf06

Thanks Fred.

The Bank 2 long term BLM was around 160. The short term was at 128 at idle but climbed with RPM. That's why I thought it was an exhaust leak.

Could the MAP being overtightened or not on enough cause those two?