OK mate here goes.
Ive got my air pump removed,,, removing it clears up some space under the bonnet and also alows you to remove some pipe work and 2 solenoids (thats the benefits , although you do need a greddy pulley set up to complete)
The air pump basically blows air into the main CAT and into the exaust ports watering down the emmisions so that cars can pass emmisions test. When you remove it because the air is no longer there the oxygen sensor in the downpipe reads all the wrong signals and so u end up with a crappy idle. (mine is pretty crummy ,, but im hoping to fix with my apexi power FC)

 

There are several fuel pressure tests described in the manual, it sounds like you tested without the motor running, by jumping the f/p termanal, and 44psi would most certainly make the car run rich at ldle. The regulator changes the pressure by referencing manifold pressure, more vaccuum less fuel pressure, more manifold pressure more fuel pressure. The fuel pressure solenoid cuts the manifold referencing for hot starts only. You can bypass it without much problem.

You can do a search on air pump removal, It's been covered many times

 

Yepz...I don't plan on removing it...I still have a cat down there. Just wondering.

 

Doh..double post...mods, please.

 

(I noticed you said you have had the battery disconnected..........don't forget to press the brake pedal for 20 seconds with it unhooked to reset the ECU)

 

Set your base pressure on your regulator to 40psi (start the car and pull off the vacuum line on the regulator and adjust your pressure to 38-40psi). Put your vacuum line back on and the pressure should drop to 32psi at idle where its supposed to be. You have too much fuel pressure thats why you are running so rich.

R.K.

 

^This is of course if you have a adjustable pressure regulator and if not then scrap what I said.

R.K.

 

Thanks R.K. I'll do that...heading out now.

 

After two days of working through the problems and checking everything out, we believe we've figured out what's causing the car to run rich.

We replaced the air pump with Tom's spare, and I purchased a new belt because the old (but still new with only 5k miles on it) was simply too tight. So we went with a bigger belt to make adjusting it easier.

We did a compression check on the engine, and although close to minimum on the front rotor, it's still within spec. Also, the seals most likely haven't had a chance to seat and seal completly due to the fact that it hasn't been broken in yet. Still, I believe that when I sent the engine back for the rebuild, they only rebuilt the rear rotor housing, as the front is 105 and the rear is 120. Pineapple racing rebuilt the motor...it's in the car, and since we haven't run it more than 5 minutes altogether at idle, I highly doubt we damaged the front rotor (espescially since it's running pig rich).

Anyways, we did the compression check, cleaned out the plugs and wires with brake cleaner. After removing them the first time this morning, we were obviously running rich...I'm talking major. The spark plugs were brand new when we put them in the second time (after cleaning) and when I removed them this morning, they were black and caked. We cleaned them up and put them back in.

We started her up, and she started up instantly...but obviously, very lumpy. We then did some diagnostics on the fuel pressure, checking both the fuel pressure, and the fuel pressure regulator. It was obviously high, 44 for the fuel pressure check, and 42-43'ish for the fuel pressure regulator check...and what was really interesting was if Tom clamped down on the fuel line just before the pressure gauge, and reduced it to the proper psi, the car ran smooth as a baby.

Does that make sense?

Soooo...we think it's the fuel pressure regulator which is causing us to run rich. What's different today, from the other day, was that with the new air pump on, the car ran much longer, was less bumpy, and we were actually able to check to make sure certain things were working right. We also had absolutely no lights or warning indicators on...so that makes me feel a bit better.

*sigh* Mooooore money. :sadpace:

Hopefully, a new FPR will fix my problems. Anyone else agree?

 

Is the FPR hooked up to the proper vacuum source? There's a nipple on the lower intake manifold that points to the firewall - other vacuum nipples might give you problems, and the vacuum line to the FPR really needs to be ONLY for the FPR.

Do you have an aftermarket FPR that you can adjust the rate with? If you have a stock one and a big fuel pump, I've seen on TurboII's the stock FPR getting overrun with a big fuel pump, making the fuel pressure more than it should be.

The "clamp the line" trick is definitely telling you you're on the right track on the problem.

Dale

 

reduce your fuel pressure and replace your plugs. cleaning plugs doesn't work very well. Trochoid in the FB section has media blasting equipment and he has a hard time cleaning fouled plugs.

 

pinch the FPR vacuum line and see if the idle smooths out or gets worse

 

I don't think the FPR has a vacuum line, does it Mike? You had the UIM off yesterday. Did you see a vacuum line? If it does, Dale might have a valid point; the FPR might be hooked up to the wrong vacuum source. One thing I noticed too was when Mike revved the motor the fuel pressure would change indicating to me that the FPR is working (somewhat). As the RPM increased the fuel pressure would increase and then suddenly drop almost as if the FPR is compensating for changes in fuel demand.

 

Isn't the purpose of the fpr to keep the pressure consistant except for when under boost conditions?

 

We did. See above. I have the stock FPR, so I can't make any adjustments. I don't consider the plugs to be part of the problem, as they're working fine...it's just that the engine is getting too much fuel. That's the problem.

Dale, I think you're on the right track...I'll double check the vaccum lines in that area again. I honestly couldn't see much of it when I took off the UIM, it's so far down there. Working on an FD is pretty difficult when it comes to getting down underneath there...so much crap everywhere, IMHO.

Also, does anyone have a recommendation for a replacement for the stock FPR? I tried Rotary Extreme, but they're still not accepting orders.

 

I'm putting a few things off, but since I have to go meet with Tom B. tomorrow, I figure I can try and knock out the installation of this little bad boy.

And yes, it's been since October since I've last been able to touch the car. Hopefully, this does the trick, otherwise it's definetly something else.

I also got hooked up with a Setting Meter for it...which will help out.

I hope the install goes easy...it'll be harder taking the whole UIM off to get to it than it will to install it, methinks. Wish me luck!

 

no mention of a fuel pump so i will start there.. if it is the stock fuel pump then there is definitely an issue with the fuel system causing high pressure either with the vacuum line not being correctly routed to a vacuum/boost source or a blockage in the system somewhere. now that said if you have a larger fuel pump like a walbro then the fuel pressure will rise normally and the only way you can drop it is with an adjustable FPR. the stock FPR will raise pressure if it is not connected to a vacuum source so i would start there and get the engine running and check to see if vacuum is being applied to the line.

next, you must keep in mind you HAVE to keep RPMs up on a fresh rebuild with used housings to give the seals time to seat in. your difference in compression between F/R is more than i like to see even on a rebuild and probably a main reason why it is "hunting" at idle and caking the plugs as well as running rich in combination with slightly raised fuel pressure.

what you have to do is get all the other misc crap sorted out and then get the motor running again and ready for a decent run in(approx 15 mins at least up to 30 minutes of high idle) and either hold the throttle open or adjust the idle screw to keep RPMs at 2000 RPMs or so for 15-30 minutes, this will give things time to seat in and idle will improve if compression steadies out.

i generally will throttle up the engine a few times from 2000-3500 in quick revs after about 10 minutes to expedite the seating process.

you really should not assume the engine is running rich if it only has a short while of run in time, it just needs some time to get everything set up internally.

as far as the alternator is concerned, get a DMM and check the voltage, simple and easy to tell if the alternator is being overworked. my initial impression of the sound was that the alternator pulley was loose and could also be why the alternator is getting hot.

 

Wow...thanks for the info Karack. I'll pass this on to Tom (REH)...

I've got a few problems now. I honestly haven't run it for that long, because for some reason, my fans aren't coming on till it's about 226 degrees!!!! That can't be normal. I have the stock ECU and I purchased the fans from someone on the board...they run with the ignition on until the car cools...but as soon as I start the car, if they're on, they'll shut off. They'll kick back on at about 226-230'ish. What's our normal operating temp for the engine?

Here's the rest of the problem...The idle is really rough, and the engine has some shake to it. Compression is 105 front, 120 rear. Smooth acceleration throughout the revs, no idle hunting, idles around 800-900RPMs. No black or white smoke. It has a very mild streetport, catback exhaust, and that's about it for performance mods. Here's two videos of it running...this is pretty much what's wrong with it.

http://www.hawaiitalks.net/images/mi...o/MOV00018.MPG

http://www.hawaiitalks.net/images/mi...o/MOV00020.MPG

Any advice guys?

 

Hmm...we messed with the Fast Idle, but didn't go so far as what this thread does:

https://www.rx7club.com/showthread.p...highlight=fans

Maybe that's it?

 

Yeah, been waiting for you to post new vids since the install party. Glad to see that it is at least running again. Oh and 226 sounds about right if you didn't install the miata or fc switch mod.

 

Not to be an *** or anything but!

White smoke is- coolant
Black is- fuel
Blue is- oil

At least that’s what I was taught.

 

Ahhh...really? I was thinking that was extremely high! So normal temp for the fans to come on is usually around there? If that's true, I feel SOOO much better. I thought there was something wrong with the dang thing. Any confirmation on this guys?

I took about 3 months off due to all the stuff going on with Drift Session and fighting for the new track, plus going to Tejas for a bit.

Now I just have to figure out what the hell is going on with the rough idle.

I have a PFC, but the maps on it are way off...(timing is like at -50 degrees or something nuts like that). Should I plug it back in? I just want the thing to work...so I can drive it. It's been down for THREE years, if you can believe it.

 

Yeah 108c = around 226f, I recently put in the miata switch in mine and now the fans come on at 206f
Oh and you could just reset your pfc to base map through the commander but you would lose what ever settings it was tuned for.

 

Thanks for the info again...I'll see about messing around with the TPS/Fast Idle tomorrow.

 

as far as the idle is concerned, i don't recall reading if this is a stock ECU or a PFC equipped car. the stock ECU has a leaning curve to it so it will run rather erratic for a short while until the car has been driven a few dozen miles to re-learn the sensors. i ignore any rough running until the engine has been test driven for a short while, if it still doesn't clear up then i start poking around and pulling codes. the PFC is rather touchy with its base maps and will have a lumpy idle if it is set too high but not nearly like the stock ECU will hunt, much more forgiving to high idle settings..

when adjusting the idle as well be sure you are adjusting the correct screw, there is 2 adjustment screw on the throttle body, one with a long shaft bore and flat head screw in it that goes directly to the throttle cam and a smaller 8mm locknut with a short flat tipped adjustment screw, this shorter adjustment screw is for the secondary throttle plates and will cause a rough idle if this is used to adjust idle vs the true idle screw. the secondary throttle plate screw is only for setting secondary throttle plate stop and should barely be touching the stop cam for it as the secondary throttle plates should basically be completely shut at idle or they will draw in air, air which is not mixed with fuel since the secondary injectors only come on at higher loads and this will affect idle quality.

and yes, with the stock configuration the fans don't turn on until the engine is rather warm, 220-225*F. with the PFC this can be reconfigured to lower the turn on temps but requires a datalogit to make that adjustment.