Map Problems

[CSXT404]

88 CSXT (SMEC). I have had MAP problems since I have had the car (August 04). I have a brand new motor, turbo, and basically everything else. I am still getting code 13, but I tested them and here is the weird part.

We took a rigged test light (parking light w/ wire) and a wire from the battery and touched the wires from the map to the wiring harness. I would hold the wire with the light and he would touch the pins in the wiring harness of the SMEC. Each one would light up as we touched the corresponding wires.

The map sensor wiring has to be off, and I am just thinking of rewiring the harness to the map sensor.

What is the proper/best way to do this? How does the wire connect to he harness or pens? Could someone tell me or show me a diagram of how to do this? It is the only thing I can think of. It doesn't make sense that the wires were carrying a current and lighting up and not working properly when plugged in to map & computer. The computer is good. I have tried 2 different computers too.

Any ideas??????????????????

[xrattiracer]

you do realize that code 13 is for map vacuum, not map electrical right?
check the vacuum system to make sure a hose hasnt come off, or gotten a hole or such. basically the ecu is seeing barometric pressure (atmosphere) when it thinks it shouldnt (engine is running, baro read solenoid NOT energized). you might also check to see that things are hooked up right, especially the baro read solenoid. maybe its even bad, who knows. bypass it temporarilly to see if that helps. run a new line from the map sensor straight to the intake manifold. if that doesnt do it then maybe the map itself is bad.

[CSXT404]

I already swapped out a baro read solenoid. I have been having this problem for a while now, but the motor went and I had the car apart during the rebuild.

Here is how my vacuum lines go:

1 Vacuum port on intake T'd to boost guage and baro read solenoid-->Map sensor.

2 Vacuum port on intake T'd to Accufab AFPR and top of boost controler.

The line out the bottom or side of boost contoler goes into a T at the wastegate and turbo. It didn't have orifices in the lines, but I put some in with no change. I took them out again now.

That is my vacuum set-up. Only getting 2 psi

[zlancer]

one problem i was having and getting code 13 was i had my boost controller hooked up to a vacuum and boost source so it was bleeding off my vacuum through the boost controller. I hooked my boost controller up to the intercooler piping and it fixed my vacumm problem. i still get code 13 once in a while usually when i'm decelerating. i can't figure out why.

[tenacious84]

haha, i've been living with code 13 ever since i bought my car last june. not only does the check engine light comes on, but the car likes to cutout sometimes while accelerating. kind of a pain in the ass, but i bought the car for $300 and put on 8k miles, so i'm not going to complain

but if someone wants to tell me how to fix it, i'd be open for suggestions

[minimopar]

The ECU is complaining about the MAP sensor reading under certain conditions that should give a known reading. Often it is caused by sluggish response due to a small vacuum leak or some non-stock vacuum plumbing. The 1989 SMECs are the most picky, I have noticed. Also check for fuel in the FPR vacuum line.

Most of our cars don't have the 1-to-4 or 1-to-2 rubber to plastic vacuum line adapter that came from the factory. They harden and fall apart. The idea there was to isolate each vacuum circuit from each other and give them each a dedicated line to a point that is very close to the manifold source. When it breaks and gets replaced with a bunch of Ts, you lose that isolation.

You want to give the MAP and the FPR their own vacuum lines that terminate at the same point, very close to the manifold. That point should be connected to the manifold via a large line. All the other crap can all share a line that can terminate at the same point. I usually replace the stock piece with a short peice of 3/8" brass tubing that has four 1/8" short pieces of brass tubing soldered in one end. This gets connected to the manifold with a short peice of 3/8" fuel hose and the four 1/8" tubes connect as follows via 1/8" ID vacuum hose:

1) Baro-read/MAP sensor
2) FPR
3) Boost guage
4) EGR/Canister Purge/Boost solenoids

If I'm using a grainger, I try to give it it's own line too, since it is basically a bleed on the system.

Hope this helps.

[tenacious84]

Quote:

Originally Posted by minimopar The 1989 SMECs are the most picky, I have noticed.

imagine that, my car is an '89 spirit t1