Just talked to my buddy at advance auto parts, if the egr doesnt solve my problem he will let me return it. I will pick up some iso heat and an EGR and report back when I am done fighting with the egr + gasket putting the new one on [&:]

 

The SCFI motors (mid/late '95 change over) do not have an IMTV. In your case, you do have one and that is what we are talking about. The plenum of a CPI motor is split into two different halves, right bank and left bank. The function of the IMTV is to connect those two banks at a certain RPM. What this does is removes the restriction at higher RPM that having the banks separated encurs. With the banks separated, at lower RPM, the torque curve is boosted slightly, however, this hinders high RPM power which is somewhat alleviated by the IMTV opening.

You may be able to check that the EGR valve is, in fact, the cuprit. If you have a small plate of steel and a drill, you can fashion a block off plate to temporarily use to eliminate the EGR valve from the system. This would either rule out the EGR valve as the cause or fix the problem, meaning that the EGR valve is at fault.

Now, before anyone jumps on me about blocking off the EGR valve, this should only be done temporarily as a test. EGR gasses actually serve to reduce NOx emissions by cooling down the cylinder temps. It does so by displacing incoming volitile air with innert exhaust gases which cannot support combustion. This not only serves to reduce the emissions of the vehicle, but the reduction in cylinder temps also extends the life of the exhaust valves. So use this as a test to figure out if your EGR valve is truely at fault before dropping the coin.

*EDIT* - Ah well that's cool. So you don't have to do the whole block off plate idea then. That'll work as well.

 

Alright, it's been on for about 2 hours...part of which was me driving around town. First impressions are that it's fixed. I put the new egr in along with some iso-heet and some fuel injector cleaner, wawa has been dispensing watered down gas these past few weeks so I think thats part of it.

Fired it up, a little rough but evened out, drove out of the driveway (about 150ft long) and it ran good..pulled out on the street and as soon as it shifted to 2nd it bogged down but never as bad as it did before and it cleared up after about 3-4 seconds. I drove for roughly 20 miles after that, stop and go, all speeds including up to 70 with NO problems, truck ran great! Turning onto the street I live on, I stopped at the stop sign, then hit the gas to turn and it sorta shuddered for a second and then took off. Aside from those two things it seems to be doing good. I just fired it up after an hours rest, little rough idle but evened out after a few seconds.

Should I be worried? I hope it doesn't persist or get worse.

 

Now i'm having a timing issue, the accel cap and rotor came in and I attempted to install it, with no luck. It doesn't want to fit on correctly but when I did get it straight (looking at the clips at the back over the ignition module) and having the holes line up, the truck will not fire. In the middle of messing with a stupid cap for over an hour, I moved the wires around so much to were I forgot where they went (lol). Anyway, putting the regular sorensen cheapy cap on and the truck starts right up but runs as if the timing is off, rough with no power.

Starting from the front right and going around counter-clockwise I have it set like 123456. I am assuming from the drivers side it's 1-3-5 and passenger 2-4-6. So assuming firing order is 612345, I have the wires on there. I have been messing with it for 3+ hours yesterday trying to get the truck to run right. Something must be wrong, any ideas?

EDIT: Forgot to mention but was obvious, inno way shape or form could I get the Accelt cap and rotor to do ANYTHING.Fits like crap and even when it's on there perfect it wont do anything. I haveinspected it and everything looks fine.

EDIT 2: Removed all spark plugs and checked to make sure they were all gapped correctly, they were. All were soaked in oil, mainly the driver side and the passenger side just had a little oil. Is this something I should be worried about? I cleaned them off well and started the truck and it's still running rough, no power like timing is off or a vacuum leak. I don't know what to do if it is a timing issue...and I can't find a vacuum leak to save my life. I pulled the vacuum hoses off the back of the intake manifold and plugged it and it seems to run better, but as soon as you hook the hoses back up the motor seems to stall. There is 4 hoses running off of the one vacuum connection, (two tee's), is this normal?

I put accel wires on it yesterday as well as the cap (which is currently awaiting return to advance), I swapped them back out for the 7mm cheapies and it made no difference. Someone please help, my main car is at the body shop because my wife wrecked it so I have to take to train to work my 9-7 night shift.

EDIT 3: Let it warm up. Still ran rough. No CEL. Still a rough run, not a low idle but sorta a put put like it's not enough fuel or timing is off, seems to be firing fine but I really can't tell. I guess I will take it somewhere tommorow and pay out my a$$ for them to tell me what it is.

EDIT 4: still not running right...could the rotor hitting the inside of the cap have thrown the timing off? I think that's the issue.

 

Heres an update. Took it to a shop yesterday to have it timed and checked out, they charged me $133.50 just to tell me nothing was wrong with the truck. This guy actually said that. Anyway, on the way there the truck had heated up and mysteriously just stopped shuddering. As soon as I start it this morning it starts it up again. It must be related to the truck being cold.

So it went in to another shop today. Timing was off a little bit, wont tell me what else he fixed just says a lot was messed up and they believe the ECU is messed up. Either way, it wont be ready until at least tuesday so now I have to rent a car for my 1800 mile trip to georgia and back tuesday. What a pain in my ***....i hate my blazer.

 

So after the shop spent a week not having a clue what the problem was while charging me out the ying yang, I got it back. I have replaced the whole fuel spider kit (thanks to info on here), as well as the ecu and timing gear + chain. problem is still irratic and unpredictable

 

let me get this straight...after all that, you're still havin the same problem? i'm not sure and i might have missed it but after reading ths entire post, i don't believe i saw that you have replaced the fuel filter. correct me if i'm wrong though. just a suggestion.

 

Have you had the distributor out? If you have, did you check the condition of the gear on the bottom? I have seen a few of these gears crack creating some pretty weird symptoms. Have you verified the base timing? To do this, you need to disable the electronic advance.

While a new fuel filter is cheap enough, I don't normally attribute idle issues with a fuel filter issue. Typically if a filter is restricting the flow, there will be more high rpm issues than at idle simply due to the flow requirements.

 

Fuel filter is brand new, sorry for leaving that out. Distributor is under a year old, have pulled it out and checked it over, no cracks and the shop set base timing when they had it.

Pulled the upper plenum off today, there is some serious runs in the carbonation on the drivers side by the in/out fuel lines, and a few puddles of fuel. On the drivers side there is no sides of runs of the carbon, it's thoroughly gunked up, but it's also got two small puddles of fuel in there as well.

I went ahead and ordered and AC Delco spider kit and a fuel line nut kit, and picked up the intake gasket at AAP today.

Will update when stuff arrives.

 

Did you do anything about the oil on your plugs? (mentioned in the post on the 23rd). If the valve cover and spark plug gaskets are leaking onto the plugs nothing is gonna fire properly - which would by why the power loss/rough idle. You may be ablwe to find out if that is the problem by pulling the plugs out, cleaning them, and then dumpingin one of the seal conditioning lubes (theyre allt he same in my experience). Run it for ten minutes and see what happens. Those dont last long though, if it is the problem youll have to change the seals. Course, if oil on the plugs is the problem, it should show in your exaust.