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Low MAP voltage??


skalor

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Ok, I'm having a problem with my turbo Lumina project. I got everything in and it runs, but it runs really crappy and I keep getting a code 33(low MAP voltage). I've checked that the MAP is getting the right voltage to it(5v), and it's ground is fine as well. I've check to make sure that the MAP wires go to the right pins on the computer and they do. I've double checked all of my engine grounds to make sure that wasn't the problem. I've ohmed it from the negative battery terminal to the TB & waterneck and both were 5.6 ohms. I've swapped MAP sensors from my other TGP and it still has the same problem. I don't know where to go next as I've run out of ideas to try. I might swap out the computer today for the actual TGP computer, but I don't think that will get me anywhere. And I put in the stock TGP eprom so that's not the problem. Also, I pulled the vacuum connector(the 4 line one on top) off of the TB and there didn't seem to be too much vacuum there. I was thinking that this might be the problem, but I never had that problem before swapping the engine. Anyone have any suggestions?? :?

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There isn't going to be much vacuum up to as these are ported vacuum sources. Only the one for the map sensor should have any vacuum, and at idle it should be pretty significant. You need to find out what the voltage output of the map sensor is plugged in at idle. Should be around 2 volts IIRC. the center one should be ground, one side is feed and the other side is return.

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Yeah, I was going to check the voltage today so I could figure out if it was the sensor/sensor readings or the wiring/computer. So, it should be reading around 2v at idle. Thanks Chris!! :)

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It turns out that the hard vacuum line that went to the map was cracked. I got that all fixed up and then the damned car wouldn't start because it had been running so rich that the plugs are now gas soaked. :roll: :evil: So, I'm going to replace the plugs tomorrow and go from there. Hopefully, the cracked line was my problem. :D

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Sounds like it was the problem. When one of my lines came loose, I got code 33 and had lots of turbo lag. I also randomly get 33 when those 4 lines come loose from the TB.

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ha...on mine...i got that same code...but it turned out to be a disconnected knock sensor.....why 33 on a knock sensor...Dunno...stupid beretta ecm...LOL. So swapping in a 4.5 caddy on the TGP?

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Well, fixing the crack in the line fixed the problem. She runs like a champ now except for the leaky x-over, but I plan to fix that this weekend. I took her out for a quick ride and holy wheelspin!! The tires are 215 comparted to the TGPs 245, and those 30mm make a big difference. Well, it is only like 20 degrees here so that could be why she's so ballsy too. :twisted: 8)

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