95 blazer runs bad
#1
12-14-2010, 11:35 PM
95 blazer runs bad
i just picked up my first chevy a 95 blazer 4.3 v6 4wd but my check engine is on did a full synthetic oil change toned down the rough idle but still runs to rich coming up with a error code po175 in bank 1 i have new plugs but not sure if i should start there any ideas to start with this is my only form of transposition and dont have much money to start replacing everything also my oil gauge goes from 50 to 60 when i step on the gas
#2
12-15-2010, 09:39 AM
Hello there and welcome....
Your oil pressure is fine...I assume it is on a cold start up?? The reason it increase as you accelerate is that the pump is spinning faster and is picking up more oil to supply to the engine.
As for the P0175 (rich condition...not enough oxygen/to much fuel) here are a few things you can try and they won't cost alot to do. Also, P0175 should be bank 2.
FYI: Bank 1 will be where piston number 1 is located (drivers side)....Bank 2 is where piston 2 is located (passenger side)
1. The MAF (Mass Air Flow) Sensor is dirty or faulty. The use of "oiled" air filters can
cause the MAF to become dirty if the filter is over-oiled.
2. There could be a vacuum leak.
3. There could be a fuel pressure or delivery problem, check your fuel pressure to make sure it is within spec.
4. Inspect all vacuum and PCV hoses, replace if necessary.
5. Clean the MAF sensor. Consult your service manual for it's location if you need help. I find it's best to take it off and spray it with electronics cleaner or brake cleaner. Make sure you are careful not to damage the MAF sensor, and make sure it's dry before reinstalling.
6. Inspect fuel lines for cracks, leaks, or pinches.
7. Check the fuel pressure at the fuel rail.
8. Check the fuel injectors, they may be dirty. Use fuel injector cleaner or get them professionally cleaned/replaced.
9. Check for an exhaust leak before the first oxygen sensor (this is unlikely to cause the problem, but it is possible)
Hope this helps.
Your oil pressure is fine...I assume it is on a cold start up?? The reason it increase as you accelerate is that the pump is spinning faster and is picking up more oil to supply to the engine.
As for the P0175 (rich condition...not enough oxygen/to much fuel) here are a few things you can try and they won't cost alot to do. Also, P0175 should be bank 2.
FYI: Bank 1 will be where piston number 1 is located (drivers side)....Bank 2 is where piston 2 is located (passenger side)
1. The MAF (Mass Air Flow) Sensor is dirty or faulty. The use of "oiled" air filters can
cause the MAF to become dirty if the filter is over-oiled.
2. There could be a vacuum leak.
3. There could be a fuel pressure or delivery problem, check your fuel pressure to make sure it is within spec.
4. Inspect all vacuum and PCV hoses, replace if necessary.
5. Clean the MAF sensor. Consult your service manual for it's location if you need help. I find it's best to take it off and spray it with electronics cleaner or brake cleaner. Make sure you are careful not to damage the MAF sensor, and make sure it's dry before reinstalling.
6. Inspect fuel lines for cracks, leaks, or pinches.
7. Check the fuel pressure at the fuel rail.
8. Check the fuel injectors, they may be dirty. Use fuel injector cleaner or get them professionally cleaned/replaced.
9. Check for an exhaust leak before the first oxygen sensor (this is unlikely to cause the problem, but it is possible)
Hope this helps.
Last edited by Frog; 12-15-2010 at 09:43 AM.
#3
12-15-2010, 07:06 PM
You will have lots of trouble with #1 & #5 specifically being a CPI equipped '95. 
I would start with a fuel pressure leak down test. From the sounds of it, you have a leak internal to the plenum. The CPI spider is notorious for leaking at the FPR (fuel pressure regulator) which will dump fuel into the lower intake on the passenger side.
I would start with a fuel pressure leak down test. From the sounds of it, you have a leak internal to the plenum. The CPI spider is notorious for leaking at the FPR (fuel pressure regulator) which will dump fuel into the lower intake on the passenger side.
#5
12-16-2010, 08:44 AM
Have you pulled your plugs? When or if you do don't go with cheap plugs. Imo good plugs are vital to good gas mileage. Although I only use the two prong plugs I can tell a big difference. Oh and being you just bought it, its always good to run some good fuel and engine cleaner through. How does it sound coming out the back? Did replacing the thermostat totally eliminate your issue as far as it running poorly?
Last edited by LikeARockBLazerGuy; 12-16-2010 at 08:49 AM. Reason: tired work twelves nightshift forgive me :)
#6
12-16-2010, 02:01 PM
i got ngk v power plugs and i did run a fuel cleaner a day ago which didn't do much i have an exhaust leak right after my first oxygen sensor and before my cat so i cant really tell but i no longer have blue smoke when its cold and my idle when stopped is at 7 to 8 hundred rpms a min and im worried its gonna die it has been at 500 rpms at idle and driving but as far as i can tell it isnt rough idle anyway and does not shake at a light
#7
12-22-2010, 06:53 PM
So you still believe you are having problems with gas mileage? Do you have any performance mods or is it all pretty basic? I wanna be clear here. So it is or isn't running smoothly?
#8
12-25-2010, 09:16 PM
okay so what i had done was had my cat replaced and welded my entire exhaust because it was leaking bad which helped gas millage a lot but yesterday i removed my egr valve and saw the passenger side of my intake was vary clean and saw puddles of gas and i wanna start with replacing the fuel pressure regulator but i dont know where to start and an idea how long it will take to do since its winter and cold out
#10
12-27-2010, 01:29 PM
It's not that bad to do. Make sure you get a new gasket and put it on when you pull the upper plenum. There are several threads on here about replacing the FPR. Here's one with some pics.
https://blazerforum.com/forum/showth...sure+regulator
https://blazerforum.com/forum/showth...sure+regulator