I think the egr solenoid on the valve cover is the issue. It sounds like it's getting stuck. It's a pricey little piece though, and don't get the wells part.

 

I couldn't get the Wells part even if I wanted to, according to AutoZone's website they don't have that part for this vehicle.

What I really wish I could get my hands on right now is a Vacuum Hose Diagram for this van so I know what hoses go where. There is no underhood sticker, and the Haynes Manual I have for this Van doesn't have one either (just Wiring Diagrams).

 

The vacume nightmare........

 

Joe,

go to any somg shop and they will print you out the diagram for free or charge you a minimal amount.

 

Aint that the truth..

It's quite the maze in there, the smog shop didn't say anything about the hoses being misrouted or anything but that doesn't mean anything, they don't even really check. Two years ago they didn't say anything about em, and the Smog Place I took it too under CAP (CA State program) said they were misrouted and we had to pay $150 for them to reroute them. For all I know that was just a fleece, see how do I know they routed them right .

As for the Smog Shop printing me out a diagram I will inquire about that when I go for the retest providing I haven't obtained one by then.

 

those vacuum hose diagrams (like printed on label underhood) always looked funny to my. They are just hose connection part of bunch of control systems. If I do not see the big picture how each system operates, it all just make no sense. <o =""></o>

<o =""></o>I would debug individual systems one-by one.<o ="">
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For instance, disable the EGR for now – it is not going to affect the CO reading anyway.

Start with the oxygen sensor – ECU – carb. Check the voltage on the input to ECU (from oxygen sensor) and output (to carb solenoid). It is pretty clear how it should work:

V(oxygen) > 1V – reach mixture -> solenoid voltage 12V (to close fuel)<o =""></o>

V(oxygen) < 0.3V – lean mixture -> solenoid voltage 0V (to supply more fuel)<o =""> </o>

The goal of ECU is to open and close the solenoid to get the O2 reading in mid range (0.6-0.9V).<o =""> </o>

Therefore, good working system would produce the following:<o =""></o>

V(oxygen) bounces in 0.6-0.9 range – mixture ok -> solenoid voltage bounces 2-10V average (solenoid opens and closes frequently to regulate fuel).<o =""> </o>

This is classical control system with feedback, and any faulty component on the chain (sensor, controller, actuator, communication) will disable the whole system.
<o =""></o>
If it is stack in one of polar states (trying to completely open or close the solenoid), you need to find out in which one and why. And you can do it without diagnostic equipment $5,000 worth. One or 2 multimeters will be just fine.
den25.

 

Ok I think i'm ready to give this a go, found my Multimeter finally, it's a Cen-Tech and does seven different functions. DC Voltage Measurement, DC Current Measurement, AC Voltage Measurement, Resistance Measurement, Diode Test, Transistor Test, etc. Not bad for the $7 I paid for it Never used it on Sensors before the probes (which are sharp btw, poked myself a couple times removing it from the box) are still kinda greek to me, not sure where to connect them at.

Sorry to sound dumb but I figure better to do that then mess something expensive up.

 

I took my carb off today and brought it to recarbo. It was tested (i watched) it turned out to be the tps (throttle position sensor). I just stuck it back on the engine and it ran good bought not really any stronger and with the same hicup type issue... I am bringing to my friends shop in the morning to give it the old sniff test.
Oh yeah, they charged me 100.00 bucks.

 

$100? thats ridiculous. Makes me wonder what i'm in for..

Right now i'm just tryin to troubleshoot everything one by one and try to narrow down exactly what is wrong before I go removing the Carburetor, and it's been tough to find time to do that lately with all this damn rain!!!! unfortunatley I have to work on the Van outside as it's too big to fit in the garage. One good thing, I finally obtained some Vacuum diagrams I dunno how much help they'll be but they're a good start got a new Repair Manual (Chiltons) between it and the much older Haynes Manual I should be able to hopefully get something done .

I did find another problem today (they seem never ending), I dunno what effect this will have on emissions but it has to do with the Thermal Controlled Air Cleaner. The Cold Air/Hot Air Valve located on the end of where the long Snorkel Tube connects near the grill is not closing. Only Cold Air is getting in even on initial startup when the Valve Door should only be letting in Hot Air. It isn't the Vacuum Motor on top I tested that with my Hand Vacuum Pump and it closed and opened fine. I'm thinkin either A. The Vacuum Hose to the motor is misrouted, or B. The Cold Weather Modulator or Bi-Metal Sensor (or both) is defective... If it aint one thing it's another.

btw sausrigging what year is your Van?

 

Joe, that's only to aid the choke in pulling off. If it runs ok cold don't worry about it. Really $100 to have the sensors in the carb tested isn't bad at all. Most places wouldn't have even gone that far, they would have charged $300 and just rebuilt it with all new parts.

 

Actually the test was free. The hundred bucks was for the new tps installed..

 

I'm not , besides the two pieces in question (Cold Weather Modulator, and Bi-Metal Sensor might as well be irreplaceable, nobody carries them, and I don't want to try and find them at the Junk Yard, not worth it.

The Carb came off today, took awhile but the rain held off at least. Alot of things to disconnect and label. Was a bit of a chore getting it off but after a few minutes and spilling gas all over myself it came off along with the spacer still attached, the EGR Valve Spacer also came off so it too will likely need a new gasket even though I was able to take it off largely intact. As for the Carb base Gasket, totally gone i'm surprised it wasn't leaking.

Tomorrow she gets rebuilt, going to use Carburetor Factory as they are right around the corner from my house and I can get everything done in one day without unneccessary traveling.

 

That gasket being bad could have caused some of the problem. Check that spacer too, they have a bad habit of burning holes in themselves. I'd probably go as far as pulling the EGR valve off and replacing it's gasket too. This way you don't get it all back together only to find that you've got an exhaust leak that close to the carb.

 

The EGR Gasket I did when I cleaned the valve a month back, the one i'm worried about now is the gasket for the EGR Valve Mount/Spacer, I wouldn't be but it came off with the Carb, everything was kinda stuck together.

As for the Carburetor Spacer aside from the caked on Gasket Material it looks ok but i'll examine it furthur once I get all the material off, I hope it's ok I wouldn't even know where to find another one thats another mystery part nobody around here seems to have. Can't count on the local Ford Dealer either, most of the stuff they carry is for newer vehicles and if they do happen to have a part I need it's way overpriced, but then again thats typical dealer.

I also noticed some seapege around the Fuel Solenoid esp where the Plug is some escaped as I was unplugging it so i'm willing to bet it's gone.

 

Ok I got the Carburetor back today, all ready to go back on the engine. The Fuel Solenoid was not the problem, turns I had the same problem sausrigging had, TPS Sensor was bad, also a Power Flow Valve was shot, Carburetor Factory tested it and said it's working fine now.

I did run into a slight setback though in the form of a slight crack in the Carburetor Spacer which I noticed once I got all the old Gasket Material and Sealent off. The good news is it's not in either of the Barrel Hole Walls nor near either hole at all, it's on the back of the spacer. I can't replace it because nobody has this part it's basically irreplaceable unless I want to hunt around in the Junk Yards for days on end. I was told since it's not in a vital area I could just use some High Temp Gasket Sealent which will also fill some imperfections on the Spacer surfaces (there are some very tiny gouges but it's otherwise smooth). I could also repair the crack with some Plastic Fusion stuff I have. I can't believe the spacer is made of plastic.