I started another thread about cleaning the Throttle body. I'm sorry to say that last night, I was impressed with how much better it ran, but this morning I find that it didn't help the cold start idle issue at all... oh well, I'm still looking!

C/YA!
Jeff

Question for you to see just how similar our problems are. When I cold start the Amigo and this is happening; if I try to hold it at 2000+ RPM's, it pops and sputters the whole time as if it isn't hitting on all cylinders. Is yours doing that as well <img src="/forums/images/graemlins/confused.gif" alt="" />

No, it's smooth, but what it will do is surge up and down by a few hundred RPM ... this evening I noticed that when I came out from work and started the truck. I was trying to hold at 1500 RPM and it would surge from around 1200 up to 1500. Did this for 3 minutes or so before smoothing out. I think if I had that sputtering I would look at the EGR valve or the BPT ...

Keep us posted!
Jeff

So I took Troopersphere's suggestion and pulled the radiator to give it a
gardenhose flush. Plenty of flow through it. Aside from the sixteen years of bugs and flotsom embedded in the front of the radiator it was pretty clean. Then I encountered a supreme Homer moment... the
"Doh!" kind. I checked the belts while I had the radiator out. Aside from the fact they were hard, shiny and glazed I had an 1" of deflection on the belt that turns the water pump and alternator. Well, no wonder it was overheating! With that belt I'm suprised the water pump turned at all. Much as I try to complicate things they always turn on the simple stuff.

And I decided to change the throttle stop while I was at it to increase the idle and adjust the TPS to accommodate the new position. Someday some one is going to have to make a tool to loosen the lower screw on that TPS. I futzed for an hour trying to angle in a phillips tip in a little box wrench then gave up, took off the EGR, took off the 19mm bolt behind it and angled a skinny flat tip screwdriver through the bolt hole of the EGR to catch that lower screw. What a pain.

Anyway, as predicted no ill effect. The idle with the stop adjusted has returned to "normal" (at least I can stop without keeping half my foot on the gas pedal), and the overheating is a thing of the past. Thanks all for really helpful tips.

And a week later I still haven't lost any coolant so it would appear the rings are my gremlin.

I'm not sure a garden hose is a real accurate way of flow testing a radiator. But if the belt was your problem and that fixed the overheating, then that's a good thing!

I am not following the Throttle Stop adjustment... isn't the throttle stop on the front of the throttle body ? and the EGR is on the back of the common chamber ? <img src="/forums/images/graemlins/confused.gif" alt="" />

I'm going to post this info over on the AUX AIR VALVE thread that I started a while ago, but it kinda belongs here also:

Saturday I pulled the electrical connector from the bottom of the valve so it would stay open. I pulled the hose from the throttle body. I sprayed some carb cleaner right down the tube. This greatly improved my cold start situation! I'm assuming that the small hole in the plate in the valve was partially obstructed. Putting a thumb over the hose to check for vacuum is NOT a good test. All that will tell you is that you have _some_ flow through the valve. You could pull a vacuum on a 55 gallon drum through a pinhole if you had enough time! In my case, it doesn't seem that there was enough air being bypassed around the throttle body to increase the idle adequately . I'm going to do it again and see if it improves some more, because it still ain't "perfect", but at least now I can get out and close the garage door without having to restart it when I get back.

C/YA!
JB

BTT for this, my problem is fixed (actually has been for a couple of weeks now <img src="/forums/images/graemlins/ignore.gif" alt="" /> )

You can see the culprit in the pic below:



The intake hose seems to be made of rubberized plastic. Mine is going on 13 years old and is developing some cracks where the vacuum lines attach. There is a metal piece in the intake hose that the vacuum line attaches to, and the cracks have become severe enough that it was pulling out and allowing a vacuum leak. I put the metal piece back in, put some high-temp RTV around all of it to seal the cracks, and then wrapped the whole thing in electrical tape. Probably better to just buy a new intake hose piece... but I'm cheap and this works <img src="/forums/images/graemlins/notooth.gif" alt="" />

Glad you got it Sean! There's a guy I worked with a few years back who always said: " 99% of troubleshooting is visual! " I believe it ...

Mine's fixed too...