xblazinlv

OK here's my problem....

If I start the car without having my foot on the gas, it will not start, and if it does, it sputters and barely stays alive and sometimes it will die, or it will slowly climb to idle, but it isn't jumping to 1500 RPMs and holding anymore like it used to before dropping down to normal idle. I have checked all of my idle adjustments, TPS is in spec, and I am running the stock start up and coolant corrections from the base map.

I have removed the AWS, ACV, and Double Throttle but still have the butterflies. I still run the ICS and have the fast idle cam active.


Here is the video, if you watch it, you can hear the car doesn't want to start. I then start it, it barely stays alive, then I give it gas for a couple of seconds and it drops down to the normal idle and stays when I let off.


VIDEO: http://www.carforums.net/vids/startupproblems.wmv

Another problem I'm having that feels similar to when it is on the dying end, is when I decellerate, the car will sometimes pass below my idle set point and stall unless given gas.


Any help would be appreciated.

nashman69g

iTrader: (3)

Do you have a PFC?

cewrx7r1

iTrader: (2)

Appears to not be getting enough air, but there are many other variables that need checking.

An experienced PFC owner should able to figure it out. Check everthing to do with idle control with the PFC first, then to the mechanical/electrical engine systems.

Contact Mark in Houma!

xblazinlv

Well as silly as it sounds, I just pulled 3 plugs and they are all pitch black. Seems they are fouled, which I guess is common as my motor is new and I've been driving around for 500 miles of break in.

I'm going to swap the plugs tomorrow and try it again, hopefully it will fire better.


I Don't know why it wouldn't be getting enough air, especially since on that start I had the idle screw turned in so that my TPS readout was at the max of 1.25 for the VTA2. My idle air bleed is turned all the way in clockwise, then back out 1/2 a turn. I tried letting more air in the idle bleed screw, but that didn't seem to help at start up, it only raised the idle once the RPM's came out and took the Power FC out of the controllable idle range with the ICS hooked up.

DaleClark

iTrader: (55)

Water temp sensor good/giving a good reading? Also go through your sensor check screen and make sure everything's in spec.

How does the car start when warm? Same thing?

Is your dashpot on the throttle body good and still there? That's a big factor in deceleration idle recovery.

Dale

Defc0n

If you figure this out shoot me some pointers , my car does the EXACT same thing

cewrx7r1

iTrader: (2)

[QUOTE=xblazinlv]I Don't know why it wouldn't be getting enough air, especially since on that start I had the idle screw turned in so that my TPS readout was at the max of 1.25 for the VTA2. QUOTE]

That is not how you adjust the TPS.

Basic starting points for idle if not working.
Page F-1, F-79, F-182 of the manual as reference.

With the cold start assist (hot wax rod) disenegaged manually( push down on the level), adjust the throttle adjust screw so the butterflies are opened 1/4 to 3/8 turn.

Have the air adjusting (air bleed screw) opened 3 turns.

You manually loosen and rotate the TPS to get the correct voltage range. Idle area voltage is more important that full throttle voltage. The hot wax rod has to be disengaged!

Start and fully warm up the engine and make throttle adjust screw changes if needed to keep it running until it warms up. Then use the throttle adjust screw to get the rpms in desired range. Use the air bleed screw to make fine adjustments that affect how the ECU handles coming down from driving rpms down to idle rpms. This requires driving and then stopping with no loads, full electric load, and AC load.

You might have to readjust the throttle screw. After all is close to what you want, recheck and manuall adjust the TPS.

Then you might have to repeat some of the above to get it correct.

xblazinlv

I did adjust the TPS in the proper manner

That's why I still had room left to play with the idle adustment screw, because i got it to stay around 1.05 with the screw completely turned out, and I was able to add some of the screw back into it later.

The TPS is spot on either way, both at idle and WOT. I spent almost an hour tweeking the TPS with my girl in the car giving me the read outs on the commander unit.

xblazinlv

Yes all sensors are functioning, water temp gets a good reading as well.

When the car is warm it starts even worse than cold. That video was a warm start.

Sorry I don't mean to sound like a newbie but what exactly is the dashpot?

xblazinlv

OK I checked the dashpot, it wasn't even close to touching the rod with the throttle fully closed. I adjusted the dashpot so that it is now touching the rod, and I verified the dashpot is in somewhat decent condition by removing it pressing it in with my finger, and watching it pop back out. It is getting a little sluggish, but it still works for the most part.

cewrx7r1

iTrader: (2)

The dashpot is always a little sluggish. It is nothing but a one way actting shock assorber to slow the throttle from closing too fast. This is to help prevent the engine from dying when you let off the throttle quickly.

ONCE AGAIN, the MAZDA RX-7 manual is your bible!!!

xblazinlv

Haha....yes it is


I also figured out why the car wasn't getting air as you said, the fast idle cam was off big time and wasn't doing anything when it heated up. I adjusted it so that before the rod opens, it holds the throttle slightly open. That should fix the problem, and my dashpot is now adjusted where it needs to be. Hopefully when I get my new idle control solenoid pigtail I can get this thing to idle perfect (I broke my pigtail and clip when i removed my manifold the last time)