Hey guys, I picked up a Blazer a few days ago. Its a 1995 with 160k on the odo. The car ran great when I picked it up, but now is having an intermittent issue. The check engine will come (flashing) and when it does, I notice a lack of power and an obvious misfire. However, when the check engine light is off (it seems to randomly come and go as I drive it) the car runs great and has a ton of power. I know this is a common problem with these, where exactly should I start? I put some premium fuel along with some Lucas fuel additive since the car had been sitting for several months and it did seem to make it somewhat better - could it be fuel pressure related? I tried to get the code read at Autozone but, even with the light on, they couldnt find a specific code. Any help would be greatly appreciated,
Thanks,
Andy

 

1995 was a "hodge podge" year for S&T body. There were 2 different fuel injection systems and 3 different computer controls used. One of the computer control systems uses a protocol that is unique, and most scan tools can not communicate with it. Diagnosis procedures are different on each system. We need to know which system you have. Do the spark plug wires attach vertically or horizontally to the distributor cap?

 

The wires attach on the side of distributor. The distributor, plugs, wires and coil look newer (as the last owner told me). The car definitely runs better with the premium and Lucas fuel treatment but still has a lack of power and shakes under 2k rpms. However, there are moments with the check engine light off that the car runs absolutely fine and has power. It seems to lessen once the car has fully warmed up and, call me crazy, but it seems to like higher altitudes affect the problem... I bought the car on a ridge and the light only came on when I drove back to my town and also I took it up on a nearby substantial bluff and the light went off completely for the most part and it drove fine. Tomorrow im going to clean the MAF, install a new EGR gasket and clean it, Seafoam everything and install new spark plugs, wires, cap rotor, a few other things thanks to Advance! Total was around $131 Online and with coupons got everything for less than $50

 

Your vehicle has OBD1.5 computer controls. That's the system that requires special software to communicate with. Use AC Delco plugs, cap, and rotor only on these things.


Have the vehicle scanned for DTC's and post them in the order they are retrieved. It would be a good idea to check fuel pressure & leakdown, this thread explains: https://blazerforum.com/forum/2nd-ge...eakdown-88305/ Post all 4 readings and we can analyze them for you.

 

Just two tips, I run the same deal. With the cap in the center of the motor against the fire wall the screws can be a bit of a b*tch. Get a roll of Teflon plumbers tape and run it around the head of the screw driver and the screw. That way you will not be dropping screws.
Before you change the gasket on the EGR take a eight inch piece of rebar or 1/4 inch extension and with a hammer bang al around it just to see if it's stuck.

 

Hey guys, I've been crazy busy but this morning I did manage to check the fuel pressure. It read 60 when I primed the pump and instantly dropped to almost nothing. Furthermore, the engine reeks of gas whenever the car is running. The FPR is definitely bad so i'm going to order a CPI spider and lines and dig into it this weekend. The only question I have is about the lines. I've read a ton of reviews that the Autozone lines do not have the gaskets/washers for the inside of the line where it meets, could I buy those anywhere?

 

Here is the line kit. Most auto parts stores have it in stock, or can get it for you.
http://www.dormanproducts.com/p-3431...origin=keyword

 

Get the updated and up graded MPI unit not the stock CPI. There is a big difference in reliability and some added performance.

 

No upgrade available for CMFI.

 

Oh yeah we are looking at a 95 I see that now.