1999 yukon need help please

[hshark]

hello everyone so this is the story. My brother in law has a yukon it would suddenly turn off while driving. The check engine light was on so I had it scanned with a local budy of mine. Map, Cam and MAf sensor all indicated problems. My brother in law wanted to replace all sensors so I did. When I was doing this I noticed the MAp sensor was disconected. Prior owner changed the fuel regulataor and must have forgotten to connect MAP. Now the issue is the yukon when I tap the gas while in drive idles to 1k rpm and goes down then goes back up to 1k rpm by itself. What can be the problem? I thought maybe MAP pig tail issue but I dont know how to test the wires with a voltmeter and I dont want to fry anything. All new parts are Map, Maf, IAC, Fuel Pump, Air temp sensor cam position sensor. I did not change the cam sesnor my father in law who is not a certified mechanic but has more knwledge than I do did that sensor. What do you guys think

 

[Big_Al]

No mechanic here but when ever I had issues with codes and sensors on past cars I was told to reset the system by disconnecting the battery. Not sure if this applies to GM stuff but thought I'd mention it in case you haven't done that....Al

 

[lesterl]

Alot of OBD1 stuff you could pull the battery cable and reset, OBD2 is a little different. If you had just replaced all that stuff and hooked up the sensor, drive it for a while and let the PCM learn and it should come back down to normal assuming there isnt another issue causing that such as a vacum leak or bad/misaligned TPS.......

 

[hshark]

yeah I did the battery thing already it goes away then comes back and starts to have that issue. I was laso thinking tps i will remove it and clean it to see if that fixes it. I will also check for vacume leaks...Any more suggestions???