A little while ago my Blazer started running real crappy. I was out of town and had to drive it 200+ miles home. I found out it was the motor (one cyl was bad). I replaced the motor with a used one that I found locally. First couple of days everything was fine.

While watching it for leaks and fixing minor problems the first couple of days everything was running fine. Now, it will start to sputter when running and while idling. Seems to be ok while its cold. At times it is fine for a brief moment, sometimes for a minute or two, then it starts acting up again. Sometimes while it does this the service engine light comes on and flashes then it will go away.

I picked up a cheap fuel pressure guage and have been riding around with it on there where I can see it. I don't really see any problems there, roughly 56psi-60psi. I pulled the plugs out, they all looked the same with no real problems.

Some other notes:
-reused old spider when I installed the other motor. the one with the motor was bad.
-new fuel filter
-new plugs
-wires not that old so I reused them
-dist. was reused but cleaned up first
-EGR very clean
-reused old intake plenum and items on it

I just ordered a new exhaust, cat included. Wasn't sure if that was the problem but I could use one anyway. On my way to order the exhaust it started acting up and the serivce engine light stayed on (flashing) longer than ever. I had Autozone try to read it but they couldn't get any code even though the light was flashing. I shut it off and ordered my exhaust. On the way home it ran pretty good for the longest time (2-3minutes) in a while.

Any suggestions or ideas? Spider, fuel pressure regulator, cat?

 

does it seem like it is running rich i.e. black smoke out of the tailpipe?

does it seem like it has a miss?

as for getting in scanned you don't have ODBII you could have either ODBI or ODB1.5. you will need a scanner that can read ODBI and ODBII to retrieve the codes

 

Doesn't seem to be rich. I pulled the plugs to see if I could see a problem with them or one cyl in particular and nothing. They aren't black and all look the same.

There's definitly a miss. I'm replacing the cat just incase it got messed up when driving for 200+ miles with a bad cyl and it could use replaced anyway. The joint where it bolts up to the muffler rusted off and I have it piped together for now.

I'm not real sure which scanner would read this info for me. If I can buy one that's not too expensive that will work for my Blazer and maybe other vehicles I will. I don't want one just for this thing because I don't think it will be around much longer. Any recomendations on brand and type?

 

mine does same thing. if you figure it out holler at me . oh yeah i tryed fuel presure regulater its running ok but not sure it cured my problem. good luck

 

Well, it's still having a problem.. It's surging. It will be fine for a second or two then bogs a bit, then fine for a second, then bogs... Sometimes the service engine light flashes for a bit but eventually goes out. Any ideas?

So far I have swapped pressure regulators, egr valve, put on new gas tank, sending unit, fuel pump, new exhaust.

I think the damn spider is the last thing left. Could that do it?

What's a decent scan tool to buy for this thing? I go to Autozone to get the problems read but they can't seem to get any reading when my service engine light is flashing, only when it's on constantly.

 

You're going to have to get the codes read before you can figure out what's going on. Having a '95 makes it tough since it could have either the OBDI or the one sometimes called OBD1.5 (really a bastardization of OBDI and OBDII). Compare your diagnostic port under the dash by the steering column to these pictures and get a scanner for the 1995 year that matches up with your port.

 

I have a OBD II port. 16 pin, etc. What I don't understand is why they can read some codes at Autozone (when the service engine light is constantly on) for me but others (when the service engine light is flashing) they can not. I'd like to make sure I get a scan tool that can read all of my codes.

Any ideas?

I think I may try to find a shop around the area tomorrow that I can take this thing to. Hopefully a shop can hook it up and give me an idea of the problem...

 

Check your manual a flashing ses light usually means a misfire on one or multiple cylinders would think it would be followed with a code that explains the misfire. Check your IACV could cause some crazy things hope this helps. As far as the scanner my 95 says and looks like OBDII even says its equipped under the hood but isnt. Most scanners wont pick it up advanced had one that did. Takes a good one to read it

 

I just think it's going to the shop tomorrow.. I guess I forgot to add that I swapped out the IAC valve already as well.. Hopefully I can get it in somewhere tomorrow and they can figure it out. I hate having anyone else work on my vehicles but I'm at a loss here.

 

Sorry for your luck hopefully they can figure it out and it aint too bad. I like doing all of my own work too I know how ya feel. Good luck