jereman

Hi all. Not sure where to go next. I've gone through and checked, cleaned and replaced sensors, took EGR valve apart and cleaned it, ran Seafoam through it, checked timing, resolved any questionable grounds, replaced lower catalytic converter, plugs, wires, cap, rotor, etc. I was getting a few codes while I was working on it but I have resolved all the KOEO codes, stored codes, and KOER codes. I kind of threw a lot of parts at it but it's at the age where I don't think replacing any of these parts is much of a waste.

It has a hard time starting when warm. Takes a lot of cranking and then smells like gasoline. Fuel drips from vacuum lines when I'm checking sometimes. If I feather the pedal I can accelerate through the gears and mostly avoid missing, but if I step on it, it will miss and lose power. Also if I hit a steep hill or am towing a trailer it will miss and lose power.

I ordered some new silicone vacuum lines and am planning on replacing all the lines when they get here. I haven't bothered getting a vacuum gauge, just using my finger/tongue/instincts so far. Should I bother if I'm going to replace all the lines?

I'm one of those guys who knows just enough to get me in trouble, not a mechanic but not afraid of getting greasy. I've kept this thing running for a while now though. Where should I go next?

Thanks for any suggestions.

BLDTruth

I would be looking at your fuel pressure regulator and the vacuum line that runs from the FPR to the manifold tree.

jereman

Thanks, BLDTruth. I'll find the FPR, check that vacuum line and see if there is a way I can check the regulator.

jereman

I replaced the vacuum line to the Fuel Pressure Regulator with no change.

I borrowed a fuel pressure gauge from the parts store but I'm having problems. Maybe others have run in to this. There is a Schrader valve (just like the valve stem on a tire) that you hook the pressure gauge to. When I thread the pressure gauge on to the test valve I get no pressure to the gauge because the stem isn't long enough to get pushed in. I ran in to this before and I was able to make it work by putting a ball bearing in the stem and threading the gauge fitting on. This time I had the fancy one from the parts store ($150 deposit, I'll be bringing this one back asap) so I tried threading the fitting on to the Schrader valve and tightening it with a wrench (13mm) to get it to actuate the stem. I'm afraid all I did was strip the male threads on the Schrader valve, and didn't get the gauge to register at all. I'm not sure if this is a common thing or not, but I haven't really resolved it at this point. The only fix I can see is replacing the fuel rail.

Anyway, when checking vacuum lines I would have some fuel in the lines up by the tree and after reading around here I think that I might be able to assume the FPR is bad without checking the pressure. Does that sound right?

jereman

I couldn't get a good fuel pressure reading, so I decided to pull the Fuel Pressure Regulator out and check it (which means I had to pull the upper intake manifold off too.) I put a length of good vacuum hose on it and gave it a few sucks. Leaky. Got a new one, checked it the same way and could get the vacuum hose to stick on my tongue for several seconds.

This stopped my starting problem immediately. Starts fine, no codes. But, I was dismayed to still have the same problems with missing under a little load. I unhooked the battery to reset the computer just in case it had "learned" to drive that way or something: no change. Double-checked timing, pulled plugs (one week old) to see if they were wet, fouled, gapped right, etc. One plug's ceramic broke coming out, one plug's threads got a little rough so I got two new plugs and put them in. I'm not sure exactly what I did; maybe a wire boot wasn't on all the way or something but it fired up and it runs better than it has years!

I couldn't be happier with how it's running right now! I can stomp it to the floor, hit steep hills, put it in too high a gear and can't get it to miss. I was going to make an EGR restrictor to help with the very common problem of missing under certain conditions, but it doesn't even do that anymore (it's done that since I bought it.) I need to SMOG it, but that should be no problem now. This thing is running practically like it did when it came off the lot in '91.

Thanks for the help.

BLDTruth

Glad it worked out!