cruiser54

I don't know.

Have you replaced the fan clutch? Got a shroud on the mechanical fan?

Refresh the grounds, clean the C101, refresh all connections, clean the throttle body and IAC. Then, check the TPS adjustment on the engine side connector.

19 to 39 PSI.

Just a thought and I know you say the plug wires are in order, but could they all be off in one direction by chance?

T into the stock oil sender location for oil pressure, or just eliminate the idiot light sender I assume you have. Standard pipe threads there. I would use the rear of the head for water temp. Again, standard threads there, to. As for the pan, it's totally unnecessary as the AW4 is as hearty a trans as you'll ever find.

It's fine. Take 2 of the long old headbolts, cut the heads off and use them as guides when dropping the head on.

If you indeed have the pressurized bottle and have purchased the Volvo cap, be advised that you must push down a bit on the cap before it grabs the threads on the neck. Also, most parts stores warranty the pressure bottle as lifetime.

Yeah. Probably. Is the hole in the manifold plugged with something like an old spark plug?

What engine and trans?

Sure does. If not, you will have high fuel consumption and idle issues.....

If it's a Renix era MJ, 87 to 90, click on the link in my signature and have fun.

That stuff works pretty good, doesn't it? Got rid of lifter tick in 2 different 4.0s for me.

Oil filter adapter seals may be all dried out and hardened.

Cruiser’s Renix Throttle Body Butterfly Adjustment Okay. Let's start from scratch. First off, that's not an idle adjustment screw. It's a throttle butterfly stop screw. It's purpose is to allow the butterfly to be as close to completely closed as it can be without binding or wearing into the throttle body. It was never intended to be adjusted in the field. But, Uncle Bob didn’t know that, did he? Engine off. Back off the butterfly stop screw with a 3/32” allen wrench until the butterfly is completely closed. Now. turn the screw in until the FAINTEST movement of the butterfly opening is detected. This can be done more easily with the throttle body removed. If you remove the throttle body, be sure to replace the gasket underneath it after thoroughly cleaning the old one off. Revised 07/07/2012

Uncalled for ignoramus maximus statement that does nothing to answer the OP's question. Point being that HO or Renix, short shifting at low RPMs does not guarantee better mileage figures.

I want to know how YOU adjusted the idle.

No he's not. It's a Renix, not an HO. I have always shifted at 2200 RPM. My '88 XJ (287,000 miles) still gets 20 MPG, and the '88 MJ (125,000 miles) gets 18 to 19 MPG. Geez. I've only shifted at higher RPMs since these were new in 1987 and never had mileage issues. HO stands for Highly Overrated anyway. That's lugging it.

MAP line taped? Not good. If you've never replaced your oxygen sensor, do it. Adjusted your idle? Not good. And, you're shifting at way too low an RPM,

It builds pressure when cranking.

Fuel pressure low?

It did not run for a week hooked up wrong.

MAP sensor.

It's a different kind of "plastic". Brake cleaner doesn't harm it.

Spray around your intake manifold to head area and also around the vac hoses near the throttle body, at idle with carb cleaner, and see if you've got some vacuum leaks.