Perfomance problem?

[steventheseeker]

I have a 95 s10 blazer and I had a bad catalytic converter, I drove it for about 2 months with the bad catlyitc until recently I replaced it along with the muffler. My question is could driving with the bad catlytic messed up my engine in any way? My truck is running extremely rough and eating gas like crazy. I'm going to put new spark plugs and wires this weeekend. Should this fix the prolem its also putting out way to much exhaust more of a smell than a visble smoke. The next thing I was going to do was replace the O2 sensor and hopefully I can pass emissions?

[mjohn]

Is this the 4.3 V6, Vortec written on top of intake?
W series...? If so does it start hard...run rich...smell more like gunpowder?
let us know...best wishes...

[RABarrett]

It is possible that the heat created by the exhaust backing up into the engine may have damaged the intake gaskets, or EGR valve. The Vortec engine showed up in '96. Ray

[steventheseeker]

It's a vortec 4.3l V6. It starts ok, not great. THe major problem is when it idles while I'm at a stop light. It shakes like crazy and I'm getting the worst gas mileage. I replaced the spark plugs and spark wires and it seemed to help. I just bought a o2 sensor and will replace it soon. Could it be my fuel injectors? I ran a cleaner through it helped a little. Thanks for your help?

[steventheseeker]

It is also a w series. what does that mean?

[Bronco2]

The Vortec was in 95 models-the W is the 8th letter in the VIN code which indicates the Vortec engine. View the Blazer/ S10 forum and you will find the same problem-leaking fuel injection parts in the plenum.

[mjohn]

Bronco2...right on ...it is hard news to break to a person...but, we must tell the truth...and the internal fuel injection parts are not cheap.....but the problem idling and pooor gas milage...indicates this problem...hands down...Best Wishes...

[steventheseeker]

Will the bad fuel injectors cause my smog to run rich, so it would fail the smog test?

[Bronco2]

Yes,it probably will fail. Also,the excess gas dumping in the system may cause engine damage.Repair this ASAP,and changing the oil and filter would be a good idea.

[steventheseeker]

Thnaks for all your help. I've changed about everything I can think of and its still doing the same problem so its definetly the fuel injection system. Is the fuel injection system a hard thing to change out? I was going to go to a junk yard or buy a rebuilt one and chnage it myself? Have any of you guys ever changed out a fuel injection system?

[mjohn]

I too am a big user of salvage yard parts...
But, the nature of this is that anything sitting for any length of time will has old gas stuck in the poppets...and regulator..and you would be paying money for the problem again...
This repair the CPI Unit with regulator is about $300. and the internal fuel lines about $40.
I tried to only use the new CPI but the internal lines were leaking as well...the good part of this is that with new lines and fuel regulator, CPI unit...your truck will run great...start great...and get the best gas milage ever...therefore saving you $$ on fuel wasted...

[mjohn]

did not mention...I am sure I could not have done this job myself..and paid an honest mechanic $165.

[Bronco2]

You can do this-It is not a hard job.If you have ever replaced a water pump or a set of valve cover gaskets you have the skills. Buy a new F.I. unit and the lines,you will also need a upper plenum gasket.I would not use salvage yard parts on this job. Remember to change the oil and filter to-cheap insurance.

[mjohn]

Yes when I got my truck running I notice the oil seems to have liquid/gas in it again...I will change it soon but is it OK to run in the meantime?

[Bronco2]

Gasoline is not a lubricant-you should change it ASAP.