Mini Van from hell

[ifixalot]

I've had my 94 Lumina min van towed three times now. Most of my other cars have never been towed.
The latest was the result of a brand new distributor's ignition module dying suddenly.
I replaced it a month ago while trying to find the cause of a surging at cruise speed which felt like a misfire.
I went through everything. I replaced the TPS, MAP, ESC, Wires, Plugs, Coil, distributor and spark knock sensor too.
Finally, I found the EGR was opening at the wrong time so I ordered a new solenoid. My EGR works off vacuum.
After installing the new solenoid, I still had the same problems but now the surging had grown into a hesitation and almost
dying after tapping the gas pedal. I disconnected the EGR and the van ran fine. So I thought maybe I'll get a new one maybe not.
I read, guys block off the EGR all the time right? What could happen? So we are going on a trip up north 100 miles. We get on
the interstate and the van dies because of the distributor. Tow it back home and I get that fixed and we head out again.
Things go OK but the engine SES light is on. I figure, OK I got get a new EGR valve when we get back.
About 3/4 of the way up, I notice we can't hold 65 MPH on small hills in the road. We make it the rest of the way but I'm concerned.
So I read the codes. I had five codes. I assume it's all related to the EGR and spark knock etc. So I retard the timing and top off
with premium gas on the way home hoping it will help. Nope, it's getting worse. The van can barley go 45 mph on hills.
So I get off the interstate and take side roads home. I hear strange noises coming form the exhaust. I suspect
the cat is plugged up. We make it home and the next day, with much effort, I get the exhaust pipe off and turn it over and chucks of cat come out.
So what can I do? I beat the rest of it out and some pieces look melted. So I guess, the bypassed EGR caused too high temps in the exhaust and melted the cat honeycomb. I put the exhaust back on and hook up the EGR. My surging etc, is back. So I order a new EGR. I put that on yesterday. With it hooked up, the van seems to run OK. I have to get it out on the highway and be sure there are no SES lights that come on. I guess I leave the cat hollowed out and not replace it since the van is so old. It did seem to make the exhaust a bit louder though.
I'm thinking of getting rid of the mini van and getting something newer for more reliability. I'm getting too old for this crap.

[Money pit Beretta]

That is bad. I hear you.......after years of screwing with junk cars I've had it. You never want to give up, but sometimes your better off.
So the FPR is in good shape? Almost seems like a fuel problem. Injectors?

[ifixalot]

It wasn't fuel pressure related. I did check that out and replaced the pump about 30k ago. This FPR is a simple
spring, which I inspected. The van drove and ran fine yesterday so I'm optimistic that it was the EGR that was bad.
I still have to get it up to 55mph plus, cruise and see if I get a SES light. I may do that today.
With the hollowed out cat, it is annoyingly loud in the cabin. I ordered a, hopefully, better quality muffler for it.
That cheap POS Walker was louder than the stock factory muffler when I put it on so I'm hoping to quiet it down
with the new muffler.

[EPfiffner]

I'm a few months late to the party, but interesting story.
FWIW in my opinion I have an '05 and an '09 GM, and the nineties stuff is WAY better. The '09 has a bad cat as a matter of fact. And with those you have a constant check engine light unless you replace it, $500 part. So newer isn't always better in my experience, unless you mean new new. Good luck with whatever you have decided to do!

[ifixalot]

Thanks for the input. It always seems the older stuff is better then new eh?
My van is exempt from emission testing but if I had newer, it has to pass and would not with an SES light.
I guess you don't have to test? On my daughter's 96, the SES light for the convertor was due to head gasket leaking.
Are you sure your head gaskets are OK?
I've been looking at newer stuff. Honda mini vans have had transmission problems.
Toyota Sienna have had door problems that cost a lot to fix.
Then I thought about Hyundai with that 10 100k warranty but perforation, (rust through) is not covered for more than 5 to 6 years.
My niece has a 2012 Chrysler town and country. It's been good to her but now little bubbles in the paint are popping up around
the wheel wells. So I guess rust still comes through at 6-8 years like always.
In the meantime, I noticed a noise in the front right on my mini van when I hit bumps. I found that the sub-frame under the rubber doughnut
had rusted away and the sub-frame was drooping down. So, took off the doughnut, and whipped up a patch and welded it on.
It seems to be holding up fine. But I think I'm pushing my luck now. Funny how it rusts under the rubber and you can't see it.
I bought a new cat a couple weeks ago, I hope to put it on soon but other things keep coming up. My hollowed out cat shell
has a hole in it so I have to do something before it gets too loud.
Maybe I should buy a one to two year old whatever, and trade it after 3-4 years before rust pops out.

[EPfiffner]

The way the newer ones like mine work is there's an upstream and a downstream O2. The upstream fluctuates 0 to 1V as we are used to with our old cars. The downstream is supposed to stay steady, around .5-.7 bolts. This is how the computer "verifies" the cat. If the downstream is fluctuating (like mine is) it throws a "catalyst efficiency" code. No inspection where I live luckily.

I was thinking screw it I'm done with GM, but as you point out Toy and Honda have issues too.

I agree with you though there comes a time when they just have to be retired when you live in the salt belt. I miss my S10 blazer but everything was just getting too rusty to work on.