My 1987 Mercury Colony Park

[BigMerc96]

Again, no experience with box TBs, but I've pulled at least 3 different variants of the 70mm truck TBs for the aero/whales. 1 has no hole, one has a small hole, one has a 3/16" hole. All from Econoline vans of varying years with either a 4.6 or 5.4 with the tall "truck" intake. There is some purpose for it, there has to be, otherwise they wouldn't do it, but what that purpose is IDK.

[sly]

Maybe it's simply a tuning thing to make up for imperfections in the TB castings. *best guess*

[DerekTheGreat]

That sounds like the stock lopo style. The HO one is about 3/16 IIRC.

Odd. TB is definitely the larger HO one, just with a small air bleed hole it seems. This one came off an ‘89 Mustang GT.

Like with the F150 I6's, I discovered HO's got different sized bleed holes as well. Several years ago I got lucky in that 3 HO equipped Rustangs were at a yard. I peered at all three and took the one which had the narrowest diameter hole. Two had the larger hole you could practically fit a Bic pen through.

[gadget73]

I'd love to know exactly how they decided all that. There must be some reason to it otherwise some of the cars leaving the factory would have screwed up idles because of it. I've never noticed a cal sticker, part number, or any other indication on a throttle body that might shed some light on it either.

[Kodachrome Wolf]

Car decided to show it's ass today.

Needed to use the horn, got a short blast and then popped the fuse. I’ll check the grounds for corrosion and the steering wheel slip rings.

Also wanted to do the O2 sensors since I don’t know when they were last changed as they looked fairly old. They were certainly old, and badly stuck. Only got the passenger side done. The driver’s side will need equal persuasion, but I’ll do it later. FWIW, a two foot breaker bar and a three foot pipe were used to get the passenger side undone. Not cool.

I also noticed a lot of green fluid on the passenger side and noticed it was running down from the vacuum lines to the EGR. I thought it was coolant, then I realized it was PAG oil. It seems the accumulator is leaking some around the clamp that holds it in place. I guess debris got under it and has worn a hole with age. I’ll have to get the system evacuated to have that replaced. I unplugged the compressor to save it from damage for the time being.

If the region was any cooler, I’d forgo the A/C, but it’ll be hot in a few months, so it’s something worth fixing for me.


I’ll get the red car out tonight and drive it until I fix the coolant weep and the other O2 sensor. I’ll call someone I know about the A/C so I can get that sorted.

[sly]

Last time I had a horn pop a fuse... one of the horns was almost a short circuit. They made noise though.

[Kodachrome Wolf]

Last time I had a horn pop a fuse... one of the horns was almost a short circuit. They made noise though.

Since I need to check the grounds, I’ll likely be removing them anyway and I can hit them with a multimeter. They sound normal to me, but this isn’t the first time it’s happened. Nick has it blow before I got it, but it hadn’t been an issue until today.

[DerekTheGreat]

Last time I had a horn pop a fuse... one of the horns was almost a short circuit. They made noise though.

This. I think mine were measuring <0.3 ohms. I believe book says they should be anywhere from 0.8-1.1. Get them to stay better than 0.6 and you should be OK. Best to test using spare battery. I found after using the adjustment screw to dial them in, that they would change once I honked them. Takes a lot of fiddle fettle. I could have bought new ones but I liked the look of the old ones.

[sly]

I have one horn at 10 ohms. The other was at 1 ohm. The 1 ohm was the one tripping things since it was a 15 amp fuse. 14V... 14 amps through one horn and 1.4A through the other. 15.4 amps doesn't pop immediately... but it does pop it.

[DerekTheGreat]

I'd love to know exactly how they decided all that. There must be some reason to it otherwise some of the cars leaving the factory would have screwed up idles because of it. I've never noticed a cal sticker, part number, or any other indication on a throttle body that might shed some light on it either.

Yah, me too. I wasn't expecting that kind of goofiness with the I6, that's for sure.

[Kodachrome Wolf]

Got some work done over the last few days. Several days ago, I checked vacuum at idle three ways: Idling with SPOUT out, Idling with SPOUT in, and Idling in Drive. The car had a tendency to lope with the SPOUT out, IAC seemed to be trying to find a happy spot (aftermarket one, but I snagged a Ford one for free today, so I may swap it), so the vacuum would go change slightly with engine speed. Vacuum was steady with SPOUT in, same with in Drive, just a bit lower since the engine speed was reduced. I've got 20 second videos of each, but the gauge was generally steady so I don't feel there's something nasty like a misfire occuring or something up with the valvetrain again.

I also verified timing was at 10* BTDC with the engine warm in all these conditions. I used the vacuum feed that goes down to the purge solenoid for each test. Interestingly it didn't seem to get its stumble habits while sitting in Drive during the tests. I need to get it on the road and do some testing tomorrow to check for the symptoms again.

I also got my freebie tachometer hooked up. I got this thing over five years ago with no bracket, from a co-worker who was just getting rid of some stuff he figured was junk. It's been collecting dust in the garage and I figured now would be a good time to get it working. I checked it out and polished up the lens, and "made" a bracket out of an angle brace for making cabinets. I went with column mounting. It only really blocks the 'BRAKE' lamp and a bit of the left turn signal indicator, but the other important indicators are still clear. Works good too.







FWIW, it did point to engine idle speed being possibly lower than what it should be. I was getting, high idle at ~850RPM, ~600 in Park after stepdown, and ~450 in Drive. Engine sticker indicated Drive idle speed should be 525-650 range. This may all come back around to me having to adjust the stop screw on the throttle body after the intake swap since I couldn't get the TPS in range. I may need to index the TPS's ears a bit for more adjustment so I can the idle speed square and keep the TPS in range. It may also explain why during a KOER test with the old IAC I was getting a RPM High Limit Not Reached. I'll be pleasantly surprised if that'll let me get things dialed in.

[87gtVIC]

I like the retro look on the tachometer.

You went full commitment with the screws. When I used to run column mounted tachs I used a big hose clamp so I could always "turn back" if I wanted to...like I am now.

[gadget73]

you did set the timing with the spout out only right? Setting it to 10 btdc with the spout in will make it wrong.

[Tiggie]

Tach mount looks good.

[Kodachrome Wolf]

you did set the timing with the spout out only right? Setting it to 10 btdc with the spout in will make it wrong.

Yeah, SPOUT out.

I like the retro look on the tachometer.

You went full commitment with the screws. When I used to run column mounted tachs I used a big hose clamp so I could always "turn back" if I wanted to...like I am now.

I did the same thing on the '97. I ran for a few weeks without it when I swapped the cluster a few years ago, but I got used to having it, so I put it back. Plus, I have a good excuse to look for a nicer tan column shroud for this car if I do decide to remove it. This one is fairly sun bleached and getting brittle.