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METZ
11-29-2007, 10:00 PM
I keep getting a code 13 on my new 3 bar custom cal set up in my Rampage. It is a SMEC setup from a 89 shelby Daytona. The sensor is a new delco for a 89 Trans am. At an idle I am getting 20 inches of vacuum and output voltage of .57 and it is steady, if I crack the throttle the voltage will bounce around a bit and settle in at .57, if I remove the vacuum hose I get a voltage of 1.6. I am at sea level if this matters. Do these voltages seem ok? The car keeps flashing the check engine light at an idle and is very rich, the light will go out when cruising but as soon as it goes to idle the light comes back on. I found a chart on the web site below that shows my idle volts should be .1 volts. Does this mean my new map is toast?

http://hhscott.com/93tmv/3-bar_map.htm

P.S. All the vacuum hoses are fine and no issues with the old 2 bar setup.

Thanks,
Robert

csx452
11-30-2007, 12:20 AM
Has your SMEC been reprogrammed to use a 3 bar map sensor? If not, that is your problem.
Frank H.

METZ
11-30-2007, 09:14 AM
Yes, it has been reprogrammed.

88_pacifica
11-30-2007, 10:42 AM
Thread Hijack!!!

Robert, I REALLY like that 'page in your sig.... sweet car dude... :nod: :thumb:

Dusty_Duster
11-30-2007, 12:03 PM
Check the wiring and the vacuum hoses.

METZ
11-30-2007, 12:50 PM
Thanks Nate! but don't call me dude...I'm not a stoner any more. :o Ha Ha

As for the wiring and hoses I've checked and everything is good. I checked the wires all the way back to the smec, also put a tee in the hose to the map to verify a good vacumm signal and that checked ok. I can put my stock computer and 2 bar map back on and it doesnt flag any codes and runs fine. How can I tell if this map is good? I took some output voltage readings at various vacuum readings and here is what they were.

20 vac .54 volts
15 vac .81
11 vac 1.07
4 vac 1.35
3 vac 1.07
0 (atmosphere) 1.63
Idling the voltage is steady with no variation. Is that normal?

The car runs fine at cruising speed. As soon as I let of the gas and engine goes to an idle the red light comes on.

csx452
11-30-2007, 07:11 PM
Yes, it has been reprogrammed.

Did you get the SMEC from one of our vendors? I'd give them a call and ask them why this is happening. Maybe there is a problem with the reprogram.
Frank

ShelGame
11-30-2007, 09:45 PM
He got it from me. I looked it over again, and I don't see anything that would cause the code 13. It's the same base cal I use for all of my 2.2 SMEC cals, and this is the first time that has come up. 1.6 volts is about right for atmospheric pressure. You usually won't see a change in MAP at idle unless the RPM changes.

METZ
12-01-2007, 09:37 AM
I may have fixed the code 13. I was looking at the map and was wondering why it had a large hose connection on it compared to the baro solenoid so I ran that size hose from the intake to the solenoid. I had to reduce the hose size at the solenoid. I took a test drive and this was the first time it didn't flag the code. In the manual code 13 is "No variation in map signal detected" so I'm thinking maybe the larger hose is like an extension of the intake plenum and is allowing the intake pulses to show up better at the map. I know, it sounds like BS. I still want to drive it some more to see if that code pops up again.

Rob,
Does .54 volts look ok at 20 inches of vacuum? I am still a little rich at idle even w/o the code 13. If I shut the car off when it's warm and restart it, look out, it sounds like it's running on 2 clyinders and black and blue smoke is pouring out the exaust. The tailgate is covered in soot. I'm worried about washing the rings down. Once you get rolling it clears up. I'm going to check the cts next. If it showed that the engine is ice cold when it is hot could that cause this flooding? I'm also going to re check the fuel presure when this flooding is going on.

METZ
12-01-2007, 04:49 PM
I'm not getting the code 13 anymore. I am still getting a code 62. It is still rich at an idle so I took out 5 lbs of fuel presure which made a world of difference. It probably needs more fuel taken out because it still seems a little rich. Now is lowering the fuel presure going to lean out the WOT a bit? I am using a narrowband and EGT for tuning until I can afford a wideband. The gauge is showing 8 bars lit at WOT from the begining. EGT's are 1450 to 1500, boosting at 7lbs. I have the wastegate hooked to straight manifold vacuum until this is all sorted out.

CTS - checked ok
map sensor - still suspect, is .54 volts at 20 inches of vacuum ok?
AFPR - not sure it's bringing up presure at boost. Hooking up ext gauge next.