Lancer Shelby having strange issues...

[MikeSaidThis]

Ok. I am still having issues. I have NO IDEA how to fix this car.

From the beginning, I had just got my car and it drove great... but showed a code 13.

Fixed a very apparent vac line issue... reset computer, code still showed, car started driving like crap. (not boosting properly... stumbling under boost/load... iffy idle, once in a while ... very inconsistent idle issues... boost issue always there)

replaced map sensor and fuel pressure regulator... no code for a bit... car still drove like crap. code shows back up a few days later.

Now it seems that the car drives fine... boosts fine when I first start up the car... after one maaaayyyyyybe 2 pulls.. starts struggling again. Almost like it boosts well when its cold. Now that the check engine light comes on again... it starts to idle worse when the light is on... but nothing really much other than that... just the always present boost/load struggle issue.

Only codes I am showing are 12, and 13. Does anyone have ANY ideas!? Has this happened to anyone before??

Let me know if you guys need any info to further assist me in this mater. I really appreciate any help I can get! Thanks so much!!!!

[Stratman]

Is there a strait vac line from intake manifold to MAP sensor or does the vac line go through the baro solenoid? If the later, the baro solenoid and purge solenoid look the same. Make sure vac line is strait from manifold to MAP then drive to see if your issue is fixed.

[cordes]

It is almost certainly a vac line problem. A solenoid could be at fault too.

[zin]

It is almost certainly a vac line problem. A solenoid could be at fault too.

+1 on that for my first thought...

Mike

[Mudman]

Hey Mikesaidthis, fancy meeting you here! Haha. If you can snap some pictures or draw up a diagram on how EXACTLY you have your vacuum system plumbed that would help us further our diagnosis. I believe when I installed a vac-block on my car I have a line straight to the MAP? However it's been a while since I've payed much attention to my vac lines so I could be wrong. Anyways, let us know how you routed everything

[turbovanman²]

Its possible you have the lines routed incorrectly thru the baro solenoid so as suggested, just bypass that for now, if it still comes on, and bad MAP.

[MikeSaidThis]

Well, I bypassed the baro... same problem. I replaced all of the lines from the manifold to the fuel pressure regulator (which is new) to the baro to the map (which is also new). and I am still having this issue. My biggest question is why it all of a sudden started happening. The "apparent" vac problem I had wasn't from the map @ all.. it was on the 2 lines that come off the throttle body that go into check valves and then tee into one line and then go down to the vapor canister... I replaced the single vac line. Then all the problems arose. Any other troubleshooting tips!? Anything I can try!? I am desperate!!!!!

P.S. Whats up Mudman!

[zin]

Did you try a direct vacuum line to the MAP, no solenoids, do not pass Go...? Also, you mentioned the MAP is new... Can you check the voltage the computer sees, ie scan tool? OR, try swapping out MAP from another running car and see if the problem persists.

I've had issues with MAP sensors being wrong (1bar) or going bad and reading higher voltage/pressure than reality, causing all kinds of consternation!

Mike

[MikeSaidThis]

Yeah. I did Try a direct line to the map. I have no real way to check the voltage off hand. And I don't have any other TD's so I would have no way of getting a MAP from them.

[cordes]

The map is under the hood right? Do you have any pictures of how the line is routed from intake vac to the map?

[turbovanman²]

Access to a scanner or multimeter?

What brand of MAP?

I really think you have the vac lines routed incorrectly, go here-

http://www.thedodgegarage.com/turbo_vacuum.html

[zin]

Yeah. I did Try a direct line to the map. I have no real way to check the voltage off hand. And I don't have any other TD's so I would have no way of getting a MAP from them.

OK, if you have a volt meter, you can probe the wires that go to the sensor from the back of the plug-in, it has to be connected to the sensor in order to get a reading... One wire will be a ground and so won't really read much of anything volts wise, the others will read either 5V (or very close) this is the "reference" voltage from the computer, the other wire will be the signal back to the computer to tell it how much pressure is there. The closer to 5V the higher the pressure (14.7 PSI boost @ 5Volts, vacuum under 2.5V). The numbers aren't exact, but I'm sure Turbovanman or someone will chime in with the pressure/voltage chart. But even if they don't, you can look to see if you are seeing high voltage when there shouldn't be, making your car think it is under a big load or making boost, when it is not, this is what will cause all that fuel to pour in.

With a code 13 actually showing, it's pretty much a shoe-in that it is the MAP, the wiring to/from the MAP, or the vacuum lines going to/from the MAP. So often, the MAP can be wrong, but not trip a code...

Mike

[cordes]

I believe if you are looking at the back side of the plug with the clip facing up, it goes 5v power, signal, ground.

Here is the minimopar.net page for code 13.

http://minimopar.knizefamily.net/fault/code13.html

Code 14 should show if the actual map is out of whack.

[MikeSaidThis]

[QUOTE=turbovanman;707868]Access to a scanner or multimeter?

What brand of MAP?

I really think you have the vac lines routed incorrectly, go here-

http://www.thedodgegarage.com/turbo_vacuum.html[/QUOTE

I believe I have a volt meter.

It is whatever map from Carquest... for this car (per their computers)

I am pretty sure I have the vac lines right. I have looked over them according to the vac diagram over and over. I can't figure this thing out!

What is the purpose of the small vac line off the throttle body? I see alot of people bypass it or plug it. Can I do that to simplify the vac situation?!

[turbovanman²]

[

What is the purpose of the small vac line off the throttle body? I see alot of people bypass it or plug it. Can I do that to simplify the vac situation?!

That's for the purge solenoid.

[MikeSaidThis]

mine just tees into the big line off the throttle body and then goes to the vapor canister... then a line of the vapor canister goes to the purge solenoid

[Mudman]

Just for the sake of advancement I would back-probe your map sensor as these guys have suggested, it is possible to have a faulty part right out of the box. See what kind of volt readings you get, and try giving the wiring a visual inspection to make sure everything is intact and no wires are pinched/crimped/grounding somehow. Post back with what you find

[MikeSaidThis]

Ok... now comes my "n00b" status. How do I do that? I am not sure what backprobing entails. please explain!

[cordes]

Stick one probe of the multimeter into one of the slots the wire goes in, and the other probe into another. You will have to set it for DC volts.

I gave what I believe to be the correct order of the wires earlier in the thread.

[MikeSaidThis]

Ok... I may have possibly solved the problem? Right around where all the solenoids are... there are 2 plugs connected to the electrical harness that go to the purge and wastegate solenoids.... and then there is one clip/plug unit.... completely un plugged... dangling in my engine bay. and looks like it follows those same plugs for the other solenoids.... where does it plug in?! I cant find the other end. I have looked... Any ideas? Is that meant to be unplugged? for a scanner or something?!