extreme_rotary

I got my T2 engine running in my n/a swap. Here's the scoop, today i found that the BAC valve wasn't connecting (the wiring was pulled out). I hooked that up, and the idling went through the roof. It was at about 3,000 rpm. I had the fast idle screw turned, so i reajusted it, but i can't get the idle below 2,100 rpm. Any ideas? The other thing is my car idles really rough, and backfires quite a bit. I replaced the plugs, and the same thing. The Leading#2 plug is firing irregularly. I swapped out the crank angle sensor with another one (same model), and it did the same thing. I swapped the wires of the L2 and L1, and the L2 still fired irregularly while the L1 was fine. i checked the crank alinment and that was fine. Are the secondary injectors supposed to come on at idle? I'm not getting any signal from them when i hook my a'pexi boost controller to them. Starting is really rough too. It backfires a lot, and i have to pump the gas to get the car to stay on. After a minute or so, it's fine. Once it's warmed up, it doesn't backfire so much, but i can't go over 6,000 rpm. If i floor it, it'll hit 6,000 and slowly increase (timing?). Any help would be GREATLY appriciated.

Thanks,
~Rob~

J-Rat

iTrader: (2)

How did you check the timing if it wont idle less then 2000 RPM? You need to probably re-stab the CAS

extreme_rotary

what do you mean, re-stab the CAS? I used a timing light to adjust the timing before i hooked up the BAC valve.

sickf4i

is it a fresh build? if so you gotta break in that motor. if you re-insert the cas make sure u take the cover off so you can see if it jumps a tooth when your just about that the bottom. as for the backfires have you checked the coils and tps. i changed mine and the backfires went away. hope this helps

J-Rat

iTrader: (2)

Well, unless you got the idle below or around 800, your timing is WAAAAAY off. The ECU starts throwing timing corrections above around 800-900.

extreme_rotary

here's the real good question...when the crank angle sensor is seated properly and timed perfect, with the cap open, are the arms (looking at the top) a little above the black sides, or a little below? the arms should be horizontal too, right?

extreme_rotary

i'm going to check the coils next, but what is the tps?

HAILERS

I know what I'd do first. I'd disconnect the bac. You said the idle went thru the roof once you connected the wiring up to it. It should not have done so.

When you set the idle on a RX7.......one of the first things you do is.......install the initial set coupler. That action negates the bac influence on the idle (that's one thing it does). I suspect there is something wrong with that bac. Soak it in some fuel injector cleaner overnight and blow it out.

The next thing is........the timing MUST, GOTTA BE, set with the engine idling below 1000rpm, preferably closer to 700-800 rpm. The ECU will all by itself advance the timing somewhere over 1100 rpm, I'm not sure of the exact figure. So you just gotta get that idle down before setting the timing. THEN set the idle using the bac screw and the fast idle screw, throttle stop screw etc. Normally you would not have to mess with those last two screws but it sounds like they've been messed with lately.

The turbo inlet duct sometimes develops a leak at the joint that attaches to the turbo inlet. Check for cracks and air leaks there and other places. It sounds like you've got one somewhere.

Yep. I think your timing is off due to it being set with the rev's being over 1000 rpm. Hence the backfiring.

I could be wrong, I'm not there and have not been working on the car (don't wanna either, woof, too much work).

ultradef

I just fixed this same problem with my T2 vert swap yesterday. Apparently, cracks in the TID are common on T2s and they caused my car to idle like crap. I would definitely check for vacuum leaks, especially around the turbo. It can be a pain to see all around the Turbo Inlet Duct piping when its installed, so just feel around the pipe where it connects to the turbo for cracks. Now my car idles like a rock at ~800 rpm. Good luck.

HAILERS

Your CAS SHOULD look exactly like this jpg attached in the item below ......when the marks on the pulley are aligned with the pointer. Three out of three of my cars look exactly like the picture. Set yours like the picture and you will be well in the ballpark.

http://www.teamfc3s.org/forum/showth...threadid=23226

OOOOps! I see I repeated a lot of what THE RAT said already.

HAILERS

f

driftaholic

a little below. I made the mistake of lining them up.

extreme_rotary

i don't think my BAC valve has an idle screw in it...keep in mind, this is a JDM engine. I have another BAC valve, but it is red (mine's teal), and it has different numbers on it...that might have a screw in it...should i swap them out? i aligned the CAS, as in the picture, but it is still backfiring...i heard that those oil metering vacuum lines can cause a rough idle...any experiences?

sickf4i

o by the way when you do align the cas, theres a dimple on the bottom gear and a dimple right above the gear on the shaft (its not the holes, just a little depression) align those. and look the the top of it when inserting. it should look like the pic "hailers" sent you.