Help with engine codes and diagnosis.

[Batboy]

Okay, I bought the code reader from Roe. I hooked it up and turned the car on. The reader counted 1... 2... 3... and then listed two codes. The first was 0108 and the second was 1494. 0108 is listed as Manifold absolute Pressure/Barometric Pressure Circuit High Input. 1494 is listed as Leakage Detecting Pump Pressure Switch. So, the question is what the heck does that mean? Both codes sound related, so hopefully there is only one problem. Is there some switch or relay that regulates pressure? Any ideas would be greatly appreciated. Thanks in advance!

Matt

My problem as listed in this thread.
http://vca2.viperclub.org/forums/showflat.php?Cat=&Board=UBB14&Number=629232&page=5&view=collapsed&sb=5&o=&fpart=1

 

[Ulysses]

One is the MAP. Unusually high input sense. Have it checked out. The other is with the leak detection pump system. Could be anything in that system. I would have that checked out as well. Two unrelated problems.

 

[Batboy]

I read the service manual and if there is a build up in pressure at the MAP it could cause the other failure (it's one of the listed possible causes of failure). So, I'm thinking they could be related. And since they happened at the same time I believe they are, or at least have a good chance. I also noticed that the input voltage to the MAP comes from a sensor at the air intake. Stupid question, but could this just be dirty/clogged air filters? Any other ideas? Should I just start replacing things like the MAP? Thanks again.

 

[AviP]

Did you perform the tests for P0108 and P1494? What are the results?

 

[Batboy]

Well, no. I'm not sure how to. I didn't see a test for the MAP and I don't know exactly where the Leak Detection Pump Pressure Switch or the system for that matter are. I read to vent the fuel filler cap and see if that cycles the LDP, but again, I don't know where the LDP is. Should I just open the fuel cap? and then start the car to see if it works? Haven't filled the car with gas since this happened, and thus haven't opend the fuel cap.

 

[Ulysses]

You open the gas cap, then close it tightly. Then start up the car.

 

[Jack B]

A little background - The vacuum tank located under the front fascia is charged (vacuum) from two outlets under the intake manifold, these feed two rubber tubes that combine into a tee. The tee is visible on the front of the manifold. The 3/8" tee is than reduced down to a smaller plastic hose that goes from the center of the manifold to the edge of the drivers side valve cover, from there it goes forward to the vacuum can. I believe the tank is activated by the PCM, it then draws the gas tank fumes back into the engine during certain operating cycles.

This is an active code since it is EPA related, I would think low vacuum in this circuit would activate both codes. You might want to check the gas cap, vacuum line integrity and overall engine vacuum, it should be 12-14 in at idle.

 

[Batboy]

Got it. I'm going to try a couple things this evening and see if I can get it working. Thanks for all the info. This seems to be a more complicated system then I had first suspected. Yuck!