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-   -   Likes to die when stopped.... (https://www.rx7club.com/new-member-rx-7-technical-256/likes-die-when-stopped-839222/)

buj818 05-12-09 12:36 PM

Likes to die when stopped....
 
Hey fellas.. Another noob here. I been a 2 Gen RX-7 manual xmsn owner for 3 days now. Have an 88 T2. I believe I may have a charging problem. While driving, car screams WONDERFULLY. However, when I come to a red light/stop sign, she bogs down and dies EVERY TIME. I have to engine stop, go to neutral, brake with left foot while steadily pumpin gas with right foot to keep her running. Theres a greddy volt meter that reads a constant 13.4-13.5volt range. But when I check the battery itself (at idle) with a voltmeter while running, its 14.0. With headlights on it drops to 13.7but never comes back up like its supposed to. Think the alternator is goin bad? I checked connections, and its all tight. Is this a common problem?

Aaron Cake 05-12-09 03:51 PM

It sounds like you have a bad or disconnected BAC valve and/or a huge vacuum leak. Also check the TPS adjustment. Make sure the dashpot is installed and working as well.

buj818 05-12-09 05:05 PM

Thanks aaron, i follow ya so far, but whats a dashpot?

thejallenator 05-12-09 05:26 PM

i believe he is referring to teh gauge you have on the dash/

buj818 05-13-09 03:42 PM

Checked out the BAC like Aaron had said. As it turns out, the hose from the aftermarket BOV adapter pipe to the BAC port was fine for the 5/8" port on the pipe, but was WAY too big for the 1/2" port on the BAC. That was prolly causing a massive vacuum leak. Ima jump all over it tomorrow and I will let you know how she turns out. Thanks!

Aaron Cake 05-14-09 10:08 AM

The dashpot is a small mechanical device on the back of the throttle body which slows the closure of the throttle plates. It looks like a small metal disk with a plunger sticking out. The plunger should extend quickly, but push in slowly.

buj818 05-14-09 08:15 PM

Fixed the BAC hose, and it helped nothing. Did the resistance and 12 volt check also. Passed both, and sounded/felt strong. Did a compression test today and got 70 on 1, and 50 on 2. Im hoping i did it wrong. For as good as the car runs, I never woulda guessed that it had a compression problem. I discon'd the crank angle and EGI fuse, did one trailing port at a time while holding the pedal to the floor. Sound right? The book said to remove both spark plugs though, I didnt do that. Please help. Oh, and forgot to mention i only used the conventional piston engine compression guage, not the special one that reads all 3. Confusing, i know, but im just starting to get into rotaries. Set me straight fellas!

Aaron Cake 05-15-09 10:43 AM

Compression test in the leading plug holes with the throttle wide open.

Try it again and see if you get 70 and 50. Those are very low numbers. 50 on the rear rotor could explain the issues you are seeing.

Did you check the throttle body for the dashpot issue?

If everything checks out, and compression is good, then the car may just need an idle adjustment.

buj818 05-15-09 01:15 PM

Hey Aaron, thanks a million on helpin me through this so far. Pulled the intercooler today to check the dashpot like you said to. Low and behold, one of the throttle body vac lines was missing. So I did some searching and found it hanging below. Hooked it up and the "dies when stopped" went away. In fact, I had is sitting at idle for 22 minutes before I said to myself, yeah, shes all better now. haha! As far as the dashpot, it has like a white plunger extender that pushes up and down, right? Its spongy both ways. Resistance on the way up, but comes down smoothly like its supposed to. Also, Ive read the idle adjustments over and over, and it really confuses me. How am i supposed to know which one of the many places to adjust from? Can you please give me a lil breakdown on what one does what? Also, im in a huge need of cutting fuel back. Its ultra rich. Thanks again bro!


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