Ok, I have a 1995 Chevy Blazer 4.3 auto with 214,000 miles on it. I bought it a few months ago and have had nothing but problems, I thought I had fixed everything except for the hard start, poor gas milageand rough idle, well my check engine light came on the other day so I took it to autozone and had them put it on the machine and it came up with the code P0172 "running rich". Before I spent too much money I took it to an actual mechanic and had them run a diagnostic test for $40, well it came up with all kinds of codes. P0137 (O2 sensor bank 1 sensor 2), P0300 (random cylinder misfire), P1133 (O2 sensor bank 1 sensor 1), P1406 (EGR), and P0172 (running rich). This mechanic said that he would put the two O2 sensors on and clean the EGR valve for $350.00, I thought that was an outrageouse price considering the O2 sensors were only around $60 each and take 20 minutes to install and the EGR valve takes maybe an hour to take it off , clean it and put it back, so I took it to4 other mechanics and they all suggested something different. One said it was the plugs and plug wires but I have replaced both within the last 2 months, another suggested it was the spider assembly, another suggested it was the distributor and the last one suggested it may be the fuel pressure regulator. They all have me very confused, where do I start?? Only problems it has now is that it is hard to start, has rough idle and very poor gas milage (I may get 140 per tank). Please help

 

I'd say whichever said fuel pressure regulator/spider is closest, First step is fuel pressure test see what the pressure is and if it bleeds off right away I'd strongly suggest this before throwing parts at it and wasting money until you get lucky and hit the right part. FPR and spider leaking are common on these though especially with the 200,000+ miles im surprised they havent gone out sooner.

 

Thank you for your reply. I'm going to clean the EGR vavle, have the O2 sensorstested, and use seafoamtomorrow, if thatsdon't fix itthen I guess I'll tackle the FPR and spider.

 

these may help you out when you start investigating the fpr and spider
https://blazerforum.com/m_60665/tm.htm this has the fuel pressure test explained better than I ever could
and https://blazerforum.com/m_7118/mpage...or/tm.htm#7118 this is detailed fpr/spider replacement with pictures helped me out when i had to do mine. hope it helps and good luck.

 

clean the egr out completely and do yourself a favor and install a gasket with a screen in it to prevent a re-occurrence of this issue in the future. Your EGR issue is the cheapest to address and may be causing all your other problems(maybe not also). Very in-expensive area to start-also an odds on possibility! JP[:@]

 

Well I clean the EGR vavle, itwas a little carboned up but not bad and did not have any chunks or anything, so I reinstalled in with a new gasket with the screen. Also ran a can of SeaFoam thru it and still the same problems.[:@]My next step is to replace the fuel pressure regulator, hopefully that will fix it. Thanks again for all your replies.

 

Ok first of all I want to thankeveryone on thissite so much, I have learned more from here thananywhere else......Anywayso I replaced the FPR (was much easier then I expected, thanks to this site) andnow it idles smooth, alot bettergasmilage and runs great...except for every now and again. Now after you run it from a cold start for about 15 minutes or so it starts missing like it wants to die (although it hasn'tcompletely died yet) and the brake pedal gets really hard and don't want to stop, it'll miss for3 to 5 minutes, then itstops and smooths back out, then it misses at various times. It seems to miss more often when I run it above speeds of 35mph for more than a couple minutes. My engine light did come on and it threw the code for EGR valve. So once again I took the EGR off, cleaned it, made sure there was no carbon oranything stuck in it, then reinstalledit(like I just did a few weeks ago), well myengine light went off for about a day, now it comes on at various timesalthough I haven't had the code read again (I assume it is the EGR code). Could anything else be causing this or could it be the EGR valve? I only ask because I want to be sure before I spend $123.00 on a new EGR and if you read in my first post it stated that when I had the diagnostic test done it threw a bunch of different codes when it was just the FPR. Thanks in advance for all you replies.

 

just curious when you cleaned the egr did you get the new gasket with the screen in it? solves the problem of the egr getting clogged up too easily just a guess but if it runs decent right after you clean it you may be sucking carbon back in if you didnt get the screened gasket and its much cheaper than a new egr.

 

Yes, when I reinstalled the EGR I purchased the gasket with the screen. Oh yeah and it did completely die on me about 2 hours ago. Same situation, drove from my house, maybe5 miles, got in the turning lane to turn off where I needed to go and when I started slowing down I could feel it starting to miss, well when I came to a complete stop it died, but started right back up with no miss [:@]

 

Just wanted to bump this back to the top, I really need ideas of what this may be. Is there anyway to test the EGR valve before I spend that much money?