It really looks like the rubber has been torn for a while due to the amount of dirt on the town part. But either way it just loosely fits in there. I do not have a way of checking the pressure reading on it bit I will refer to the link when i can.

I replaced the MAP and took it for a spin. A 53 mile spin(mostly to get my 1yr old son to nap) and got the SES to come back on. My friend is bringing his scanner over. Anything in particular I should be looking for?

 

The codes will give direction.

 

Okay. My friend brought the scanner over. When I first pulled the code it gave me the P0420. While I was writing all this down the Blazer started shaking and I could really smell gas. Then it gave me P0300. So I had the P420 first followed a little time later by P0300.

Here is the Live Data Read out.

RPM 571-604
TPS(V) 0.57 TPS(%) 0
O2 B1S1-B2S1-B1S3-B1S2 they were jumping around
O2 CROSSCNTS-1 20ish O2 CROSSCNTS-2 120ish
START CLNT(F) 163
ST TRIM1 128 LT TRIM1 139
ST TRIM2 128 LT TRIM2 139
INJ PW B1(mS) 4.0-4.2 INJ PW B2(mS)4.0-4.2
OPEN/CLOSED LOOP_CLOSED A/F RATIO 14.7
MAF/GM/SEC) 6.1 IGNITION(V) 13.6
MAP(V) 1.35 MAP("HG)10.7
COOLANT(F)205 COOLANT(V) 1.82
INTAKE AIR(F)118 INTAKE AIR(V)3.76
BARO("HG)29.6 DESIRED IDLE(600)
IAC POSITION 32 DESIRED IAC 32
FT CELL B1 17 FT CELL B2 17
EGINE LOAD(%)20


EGR DATA SCAN


O2 B1S1 STAT (switches back and forth from rich-lean)
O2 B2S1 STAT (switches back and forth from rich-lean)
O2 S2 READY_YES
O2 S1 READY_YES
IGNITION CYCLE DTC YES POWER ENRICH_NO
EGR DUTY(%)0 EGR POS(%)0
DES EGR(%)0 EGR POS(V)0.76
KNOCK ADJUST_0 KNOCK_0
KNOCK(V) 4.65 SPARK ADVC_21
KNOCK RETARD_0 CAM RETARD_-10
SPARK CTRL RET_NO SPARK CTRL ADV_YES
EVAP DUTY(%)0
EVAP VENT SOL_OFF FT PRES("H2O)0.21
EVAP CANISTER_OFF EVAP VAC SW_ON
PWR UP VAC PASS_NO WEAK VAC PASS_NO
SMALL LEAK PASS_NO PURGE LEAK PASS_NO
IGNITION_13.7 INTAKE AIR(F) 135
COOLANT_207
A/F RATIO_14.7 LT TRIM ENABLED_YES
DECEL FUEL MODE_NO NO IGN 1 SW_ON
IGN(V)LOW_NO IGN(V)HIGH_NO

 

Something to check that i read about while browsing this forum. It seems that about 50% of the blazers produced had crappy bearings in the distributor shaft that like to wear out and cause lateral play. This will introduce the P0300 code. Pull your distributor and see if there's play in the shaft. Just a thought.

 

Thanks Mike.

Also I forgot to post. When I was looking at the Data of each Cylinder as they fired it said Cylinder 2 misfired 4419 times and Cylinder 6 misfired 4 times.

 

Stupid question, Have you checked spark plug wire resistance against spec? Sounds like cyl 2 is the likely culprit here. How about the brakecleen/starting ether on the intake gasket near that cylinder trick?


Edit:
To me this would be what i'm looking at after checking distributor/intake gasket.
PWR UP VAC PASS_NO WEAK VAC PASS_NO
SMALL LEAK PASS_NO PURGE LEAK PASS_NO
Looks to me like it is failing vacuum tests on EVAP. but i could be reading that wrong. Not that that would cause your problem, but it points to a possible vac leak. I could be totally wrong though.

 

I'm not sure what you mean by brakecleen? I'll try anything to rule it out. Also where it the evap? Is that the purge system in the back of the blazer with the three lines? How else would I check for intake leak?

 

Nothing looks out of the ordinary with that data. The LT & ST fuel trims are likely 12.8 & 13.9, not 128 & 139, but it's odd that they are exactly identical bank to bank.

Worn sleeve bearings in the distributor and/or a worn out distributor gear can cause erratic spark. Does the scanner display the misfire count broken down by cylinder?

 

get a can of brake parts cleaner, with the engine running spray around the intake manifold gasket. If the idle changes when spraying a certain area you found a leak. It's an old grease monkey trick. you can use propane/ starting ether too but be VERY careful if you do, brake cleaner is less flammible (although you still need to be careful).

Yes the Purge system/evap system comes from the fuel tank all the way up to the intake somewere (not sure exactly where as i've not worked on it on my vehicle).

 

I have found that an unlit propane torch works just as well and won't potentially harm the plastic components in and around the engine compartment as much as brake cleaner can.