LongDuck

History: 84GSL-SE, RE-EGI mostly stock, cold air induction via Mariah headlight NACA duct to K&N filter box, PP rear muffler.

Problem: Engine idling very rough after replacement of a leaking fuel injector (rear rotor). After work performed by me, engine refuses to idle cleanly and surges, stumbles, off-idle accel is poor and fuel economy down to 12mi/gal.

Work performed to correct: (long list)
* Changed rebuilt fuel injector to another
* BCAV cleaning and rebuild
* Upper intake tract cleaning
* Lower intake tract cleaning
* '6' port cleaning (oh, man, where they grungy!)
* New vacuum hoses throughout rat's nest
* TPS adjustment (built the light 'tool', works great)
* Throttle body rebuild and cleaning, oiled butterfly pivot shafts
* New plugs, cap & rotor, air filter cleaned
* New fuel filter ($37 for SE's!)
* Timing checked and correct for SE, 13b
* New Optima battery (old one crapped out during all)

NO GO, on any of this, so... ATF!

ATF added to intake runners since lower intake manifold was already removed. Added 2 tablespoons of Castrol ATF (black bottle) for each rotor 'face' while rotating engine with 22mm socket on alternator pulley. After 6 rotations of the engine, I was confident that it was adequately lubed up. Let it sit for 8 hours. Rotated engine 2 turns, waited till next day, rotated engine 2 turns.

Replaced O2 sensor with my old one (glad I kept it!), replaced spark plugs with my old ones (those too!), and pushed the car out of the garage to fire it up.

SMOKE! Oh, man, WHITE SMOKE and lots of it! I was worried. A neighbor came down to see if my house was on fire, but with the engine wrapped up to blow out the smoke and I couldn't hear him bitching at me. Another neighbor drove by on his motorcycle and waved.

Results: Car still idles poorly, BUT, it has loads more power now than before and seems to be getting better the more I drive it (it's been 4 days now). Consider this a testamonial. This really works...

Now, to install that ATF electric pump to replace my SubZero start assist...

I'm thinking James Bond Smokescreen.

inittab

Cool!

Actually that's not a bad idea. Except, I would just install plain 'ol water instead of ATF. Water injected into a running engine is another excellent way to clear out the carbon deposits.

82streetracer

iTrader: (1)

ha ha, i wanted to do the same thing with my sub zero setup. cool to just make a smokescreen on command.
theres a thread somewhere.

Rotortuner

Ya water injection is cool. Who sells a kit for that?

CJG

82streetracer

iTrader: (1)

heres the thread.

A RX-7 idea worthy of james bond

joelwahid

i atf'ed my car the other day. i ended up using half a quart. i started it up and let it idle for like 6 minutes or so, there was a fair amount of smoke comming out. i thought "man, those guys on the forum are fulla **** it isnt smoking that much". then i revved to like 5k rpm and there was hella smoke, it was out of control. it ended up taking like 30-45 or so minutes to burn it all off, i thought it would take no more than 10 minutes, so i thought i had fucked something up somehow. anyways she runs a little better now, so i am glad i did it.

Wankelguy

Techron works better than ATF, even if it is more expensive. Clears out quicker, too. Leave it in for up to a WEEK. Try it, you'll like it! -WG

82streetracer

iTrader: (1)

the more carbon you have in your engine the longer it smokes.

if it lasted 45 minutes, i hope it made a big diffence

brownmound

Wow, you and I should hang out. Or at least, I should have been hanging out with you when you did all this. I have an 84 SE and it idles like ****, it's all off, and Im not sure where to start. The air mixture screw is maxed out open, the cruise control cable is the only thing that will hold steady idle.

I just got the RB exhaust and it backfires like crazy. LOUD! and smells horrible.

I am also thinking leaking fuel injector so I thought about sending them off to have them them all cleaned and tuned up. Since I assume you have to take the intake off to do that, I figured I would order new gaskets and all that good stuff, take it all apart, clean and lube everything, put Humpty back together again and see what happens. O2 sensor is brand new. BAC valve isn't stuck, though the AC control valve didn't click under 12 volts. That shouldn't affect the idle without the AC though.

Guess I might ATF while I'm at it...

So, any tips on doing all this goodness, since you went through it already??

Now I just need to find another car to drive so I don't have to rush it.

Right on.

LongDuck

If I were to do this again, I'd start with pulling the intake manifold off at the LOWER interface to the engine - I think part of my problems with idle were due to a stuck apex seal due to carbon crap falling down the lower intake manifold runners when I removed the upper intake manifold to work on the injectors.

Since you're going to be taking it all apart, anyway, might as well reduce the chances for crap to get into yoru engine by removing the ENTIRE intake system from the lower intake manifold, gasket, etc. at once. Doing so will also allow you to get to the intake runners in the side and intermediate housings to inject the ATF, which seems easier to me than squirting through a plug hole, and you can get to more rotor faces without rotating the engine and having ATF run out into your exhaust to make smoke later on...

Also, now that the intake system is off, might as well overhaul everything you can get your hands onto. Injectors are rarely the problem, as my 84SE made it to 160k mi on the original injectors without any problems in performance - I had to replace one due to a leaking body which was squirting fuel out onto the top of the intake manifold. This smells like raw gas when you open the hood and is very unsafe.

While the intake system is off, spray some carb cleaner into the '6' port holes and pull the sleeves out - you'll be amazed how grungy these things have gotten if you've never done this before. Took me several minutes of spinning them in place while spraying brake cleaner and using vice grips to rotate them out far enough to scrub them down. Do the same thing to the runners and sleeve holes, but be careful to scrape anything OUTWARD, not INWARD. Use a toothbrush to wash out the cylinders and runners with brake cleaner and you'll be a long way toward more performance.

Now, I KNOW those '6' ports work correctly and have recovered a lot of extra power. Get the intake gasket set beforehand so you have all the parts (upper to lower gasket, lower to engine gasket, and an injector reseal kit while you're at it - PEP Boys, Borg-Warner part, $7 investment, per injector and piece of mind is priceless.)

Post a new thread if you get into this project. HTH,

brownmound

Definitely will start a new thread. I'll try to take some digis and post the before and after while I do it. Tomorrow I'm going to take a look at things and do some more minor testing to see if i can improve the idle some. Dunno. Thanks for the advice though, I figured I would have to order new gaskets for the intake....there are only two? Sounds good to me....oh yeah and new seals for the injectors, I've read about those before too.

How long did it take you to complete the job? I like to take my time and clean things real good, but this car is my daily driver so unless I borrow a car I'll have to complete it in a weekend.

Right on. Thanks Longduck.

LongDuck

You can do this over several weekends, which is what I did. MY SE is also my daily driver, so I had to span the work out to the appropriate weekends.

If you take my advice and remove lower intake, the thorough cleaning of all intake system parts (manifolds/runners/TB/'6'ports, etc.) will take you about 8-10 hours to get it spotless (which is what I did). Only then will you know that it's operating like the factory designed. I spent about an hour polishing my '6' port sleeves, if that tells you anything. Once the lower intake system is cleaned and done. Reassembly is straightforward.

I spent about another 3 hours on the throttle body but this was to get it functioning 100%. Another hour or so on cleaning and oiling the '6' port actuators, rods, runners, etc. and it's spotless.

Get yourself about 8 cans of Brake Cleaner and you'll have some left over. While you're at it, get a set of brass bristle brushes (like toothbrush size, but a little larger) to clean the intake runners, and a stainless bristle brush to clean the outside of the intake system. This will help in the cleaning stages.

I'll watch for your new thread when you dig in. Good luck,