Idles like its got cams
 

Hers the mods..intake, exhuast, non seq, air pump removed, vaccum simplfication.

Ive been messing with this thing for about 6 months now and Im about to pull my hair out. The car run super rich all the way through the rpm range. It idle like a big block chevy with cams (lopes), low vacum pressure (10ish), and has a ton of exhuast pressure at the tip. What little I have gotton to drive the car it would only pull about 4 pounds of boost. If I could just get the very rich, lopy idle worked out I probably wont burn the car.

Heres what I dont trouble shooting so far.... Brand new map sensor, new plugs and wire, drained gas and put in new, checked for vacum leaks (none).

Any Ideas would be great, I'll try anything at this point. Thanks.

almost sounds like the same stuff im going through....almost

Compression check, number one rule of rotary engine troubleshooting. Sounds like a single cracked or busted seal somewhere. Does your vacuum needle fluctuate rhythmically at all during low rpm's/cranking/idling?

Do you have a PFC or other engine mangement? If not, removing the airpump will cause the engine to run really rich. It uses the air from the pump to "dilute" the emissions at idle and below 3200rpm. Plug the airpump back in and see if that remidies the issue. If it doesn't, then at least you can move on. But that is the #1 complaint i get from customers when they remove their airpumps..."Hey brah,dis ting runs like junk now boo!! I when take the air pump off and she when run like junk!" My impression of how the local customers sound.:D

mine tends to idle like that when cold... once it warms up its fine... pulls like a mo-fo and all. no needle flux... decent vac (though my boost gauge is alittle off) and the airpump is still connected and functioning.

my engine is a 2k old rebuild with mild port work done... could the enlarged ports be causing this?

My car had similar issues, if you have a buddy with an FD, try his ECU to see if that helps. Make sure all your vacuum lines are going to the right place.

Did the compression check and everything is fine.

I dont have the parts to put the air pump back on, it was gone when I bought the car.

No PFC on the car, stock ECU.

Just checked the TPS, it was about .4 out.

Keepem coming I'll try it all.

I did the ECU swap about a month ago with the same results.

The engine lopes at any engine temp.

What were the results of the test?

It really sounds like you have bad/low compression. Either you have low compression, or one of your manifold gaskets is either blown/missing. What are the condition of the gaskets between the throttle body and the UIM, the UIM and the LIM, the LIM and the block?

Could also have a plug trying to foul. Any chance we can get a video of startup and idle?

would a fouling plug cause lopy idle until full op temp?

yup, it can cause one to run rough (or not at all) until you get the r's up and then it'll start working a bit better. I see this alot, because I get cores in that have sat full of gas/water/oil/atf/watever, and then when it's time to restart them, you have to clean off the plugs to get them going. Even then they dont always work, and the engine just won't run right, and once you change the plugs it does much better.

This would be my guess as well...

You can find a used airpump really cheap in the for sale and wanted section.

If you get a blockoff plate, would that work instead of getting a new airpump?

It seems like it's an ECU issue. I disconnected my air pump once (the hose going from the airpump to the cat had a leak and made a hissing sound), and it did that same lumpy idle. The idle would be ~900 and then dip to ~500, at a very even interval. The timing was so precise that it makes me think it was be ECU related.

I would assume that most people who have removed their air pump are already running an aftermarket ECU, which is why you don't hear too many complaints about it.

Good luck,
-s-

I done 3 other 7s (vacum hose simplifcation, non seq and air pump remove) besides this one, with stock ECU and all ran perfectly fine. I even used one of those cars ECUs in this one and no change.

I presured the the intake system and had no leaks, very nice.

And have put a new set of plugs in the car EVERY time Ive made a change that I thought might work.

Would the block off plates make any change worth trying. I can do those very quikly at the shop, before trying to find a complete air pump set up.

The air pump missing will cause your 7 to be rich at idle and idle a little rough but does not explain the 10" vacuum or 4 psi boost.

Either you are not producing enough vacuum (blown motor) or your vacuum is going somewhere. Recheck seq siplification mods and for vacuum leaks. Check one way check valves (make sure they're not backwards too) and vacuum tank (should here pshhh sound when pulling a hose off it after running). Then check solenoids (apply 12V and listen for click).

Past that you probabely should get a compression test.