Hey i am having a real hard time troubleshooting my blazer, its running very poorly, i.e., sputtering, lack of power, i took it to a shop and they told me it could be one of three things, the number 2 fuel injector is bad, replaced it. Plugged cat, chopped it off and straight piped it. Fuel filter, replaced and found a ton of rust and crud, ive done these three things to no avail. Ive also given it a complete tune up, cap, rotor, wires, and spark plugs twic, cuz i thought i might have gotten a bad batch, the first set of plugs were bosch platinum series, took them out and exchanged them for ac delco platinum series spark plugs. I also keep getting a crankshaft position sensor ses light that comes on and ive replaced it two times and had the codes cleared and the ses light keeps coming on. I was reading on here and there was a gentleman having the same exact problem with his xtreme and he replaced his MAP sensor and it worked like a charm, so i just got done replacing mine and i still have a sputtering/no power symptoms. I dont know if this last bit of information might help, but when i pulled the first set of new plugs out they were black, oh and one more thing i also blew an intake gasket, got that replaced AND changed yhe oil twice to make sure any coolant that was in the oil got flushed out, please help!!! Im so frustrated with it im ready to drive it into a tree :/

 

Some things to keep in mind... DTC's never tell you to replace a part. The DTC tells you what circuit had a malfunction, and following the proper flow chart will lead you to the problem. Also, your MAP sensor, if there is no DTC in memory, the part is fine, don't waste your time or money replacing it. After you replaced the crankshaft position sensor did you perform the crankshaft position sensor relearn? (It is mandatory).

Have you checked fuel pressure and leakdown? If so, what were the readings? After the intake gaskets were replaced, was camshaft retard checked and adjusted? (Again, mandatory).
What DTC's are/were in memory and what order were they retireved?
What was the DTC for the crankshaft position sensor?
Does the SES light ever flash while driving?
EDIT: BTW, you were right with the first batch of plugs that you installed Bosch makes great plugs, but use AC Delco in this engine.

 

P0335 is the crankshaft position sensor and a p0440, evap emission control system malfunction. In that order as we speak. I do understand dtc's dont tell you exactly what is wrong, but the sensor itself is usually a good spot to start. And also as for the map sensor, it broke off at the gasket when i tried taking it off to do a vaccuum test on it. No I haven't done a fuel pressure test yet, that and a compression test were my next steps in my process, but i know its getting plenty of fuel cuz the whole vehicle smells to high heaven of fuel, so i know its some kind of spark/timing issue. As for the SES light, it used to flash, but now it just stays on. And lastly I knew there was something more to the crankshaft position sensor other than just plugging it in and going. damnit im pissed off at myself for ignoring that thought in the back of my head. I dont believe the camshaft retard was checked and adjusted after the intake gasket.

 

If your vehicle stinks to high heaven of fuel then you need to do a fuel pressure test like captain said. If you smell raw gas then its probably getting out somewhere it shouldn't. Do you ever have issues starting it when cold?

 

Nope it fires right up every time, hot cold warm doesnt matter the temp, once in a blue moon it will stall going from drive to reverse, and the fuel smell is coming out of the exhaust and when opening the throttle plate.

 

Smelling fuel when opening the throttle plate generally means you have a leak in the injector assembly. But when that happens it usually takes a while to start The car. So you won't know for sure until you do the pressure test, its really easy to do yourself. But it sounds like you have more than one problem including the CPS but all that takes is money to have a shop do your relearn.

I also saw that you replaced your #2 injector? I didn't know you could replace an individual fuel line, but if you did you cold have possibly damaged the rest of the assembly because it gets very fragile over time.

 

When you go to the parts store, you have an option, buy the single injector for like 55, or the whole spider assembly for like 320, i didnt have the 320 otherwise i would have just replaced all of them at once when i had the intake plenum off, but i had a cylinder #2 misfire code so i just replaced the #2 injector

 

I guess ill run to the parts store and borrow a fuel pressure tester, then post the results, if everything checks out ill run a compression test for the hell of it

 

Oh that's interesting, im assuming you were in somewhat of a hurry but i try to never buy things from part stores. Always over priced. For the future check out rockauto.com when you need parts. I know the injector assembly is less than 300 on there but still its expensive. Let's hope your regulator isnt leaking

 

It's under $180 on Amazon... for a Delphi