I was driving along today getting a little sideways as it has been raining for what seems like two weeks. The check engine light comes on and then the dreaded REDUCED ENGINE POWER shows up. 1500 rpm is the limit. All the guages look fine and I slowly make it to a friends house.

After it cools down, I remove the intake tube and install a lace on insulating wrap by Thermotec. That I hope will cool the IAT's a bit and maybe help with the boost/beltslip problem I have been fighting for a while. Installed a manual tensioner that I picked up from Texas Terminator (thanks) but the problem is still not fixed.

Back to the real problem. After I put it back together I start it up and no "reduced eng pwr" but the check engine light is on. Head up to the gas station to get the codes scaned, but of course no one is working today. As I start it up to leave, the check engine light is gone. Back to normal. ???

This happened before about two months ago. The guy said there was nothing to scan b/c the check engine light was not on. The dealer told me that if the check engine light was not on, there would be nothing to look at also. I was told that the computer must of had a hiccup or something and not to worry about it. The shop that did the work told me it was probably a glitch with the computer or possibly the map(?) sensor. Told me that if it happend again I might have to replace it. I will call them tomorrow.

It then gets worse, as I head home, it does it again. Check engine then Red Eng Pwr All the guages look good and I head to the house at 1500rpm. It will get into 3rd and do 30mph after a while. Tomorrow morning I will drive it to work and try and get it scanned. Who knows, it might run fine tomorrow. WTF???

 

well if you get a ses light,then the light goes off then the problem if not there @ that present time but the code will be in the freeze/frame records.so you need a tech 2 and you can see what is wrong

 

Any ideas on an affordable scanner so that I can get an idea as to what is happening. What is the cost of one of those tech 2's ?

 

I had a mechanic tell me that if the SES light was off there was nothing he could see. Then I go to get it checked somewhere else a few days later, after the light went out, and the code(s) were all in there. Unless you erase them with a scanner, they stay in memory. I had 6 codes from a while ago still in my memory bank. Forgot to clear them after the intake tube slipped off the TB. I don't know that there is a "cheap" scanner. The Diablo sport seems to be decent but a good one is in the thousands. Your specific problem sounds very familiar. I had a Powerdyne on my Tahoe prior to the Radix. The tune that came with it worked but not 100%, if you really got on it the computer would read too much air coming in through the intake and give me the "reduced engine power" light and just like you I was going 1500 or so rpm. If I shut off the engine and waited 30 seconds to restart it was fine, until I got on it again. You may have a tune issue. This whole episode is what drove me into getting a custom tune. Hope you figure it out.
P.S. Where in FL are you?

 

The whole setup was tuned through ls1edit, but unfortunately the shop where I had the work done is about 750 miles away. I am in Miami.

 

Have you swapped pulleys since the tune or anything like that?

 

You May Be Able To Get A Tech 2 Off Of E-bay @ A Good Price They Run 2500 New.

 

autozone will read them for free, i seriously dont think its something with the map sensor unless youve got an aggressive cam. Let us know what the codes are

 

Baum is on the right track. There's a table in EDIT (HPTuners doesn't show the table) that says there shouldn't be any more than x amount of air (measured in grams/cyl) coming into the engine for a given RPM and TPS. It's a safegaurd to make sure the electronic throttle isn't loosing control. It's a tuning issue.

I had the same problem with mine, anytime I would hit WOT it would do that and not go away until I would clear the codes. EFILive or HPT will read and clear the codes just fine.

 

Maybe I remembered wrong about the map sensor. I'll get it scanned today and check back this eve.