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-   -   DTC Map 33 (https://camaroforums.com/forum/93-02-general-41/dtc-map-33-a-81147/)

gmacsz28 04-14-2017 03:35 PM

DTC Map 33
 
Car runs good until it warms up, then when I put it into gear it will either stall or drop low rpms and will get DTC 33. Can anybody help me out with this? I also have a data log but don't know how to download it onto here. And for some reason my signature is not showing up.

craby 04-14-2017 05:00 PM

dont get more abilities till you post a couple more times. keeps the spammers away,,, sorta. 33 means the map is seeing low vacuum or sensor is failing. look for vacuum leak.

gmacsz28 04-14-2017 05:18 PM

Already replaced sensor and checked for a vacuum leaks. Also checked the wiring.

Gorn 04-14-2017 05:39 PM

Are you running a stock Map sensor on a super charged engine? Has the car been tuned for the supercharger? Low vacuum error on a supper charged car seems super charger related since zero vacuum or even pressure is possible.

gmacsz28 04-14-2017 06:08 PM

Yes it's been tuned with stock map sensor. Like I said it only starts acting up after it warms up, fans running and shifting out of park.

gmacsz28 04-14-2017 06:09 PM

I did notice on my data log that when I shift out of park, volts drop from 13.3 to 12.

GaryDoug 04-14-2017 10:25 PM

It's obvious from looking at your log file that the idle speed vacuum starts out high in the 60's kPa area and, as the engine warms, gradually rises into the 80's, when it correctly sets the code. Tuning does not adjust the thresholds for the DTC testing in the pcm. Get code 33 programmed out or find out why you are losing vacuum as the engine warms..

gmacsz28 04-14-2017 10:54 PM

What would cause loss of vacuum as car is warming up. Is there certain things I can look for?

Gorn 04-15-2017 07:25 AM

I would think step one would be to confirm the sensor is reading correctly by verifying the readings with a good hand held gage. Low vacuum warning makes all the sense in the world in a NA car as a error code, it seem like it would be problematic in a Super/Turbo car.

If the car was tuned and close to setting a code, you could be talking about a very slight change is vacuum. There is a very long list of things that can cause slightly lower vacuum over time. I would think the list of parts that would have no effect on vacuum would be shorter. Heck even a good cold morning can cause a slight drop in vacuum due to air density.

Simple things that come to mind is, hose going to MAP sensor is collapsing, Slightly plugged Cat, Slightly stretched timing chain, a dripping injector, Carbon build up in the intake. That is just the stuff unrelated to the super charger.

It would be very interesting to compare a log from before the code started to a current log to see how much vacuum we are talking. If you are talking 1-3 inchs good luck finding it.

gmacsz28 04-15-2017 07:36 AM

I have a data log but it won't let me download it yet. Map sensor is located on top of intake, there is no hose.


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