What I have:
1989 Mazda RX7 N/A
**
The Problem:
Car does not start without a lot of effort when in my driveway which is very steep… Starts great anywhere else (so far)…
It idles erratically when coming to a stop but smoothes out when completely stopped…
It bucks or lunges when coasting at an idle…
It has begun backfiring occasionally when I am at high RPM’s and I release the throttle…
**
What I Have Done Previous To The Issues:
I just put an aftermarket intake in... It is the modified prelude intake of course... Well I made my own little version since it did not seem to fit the way it was pictured in the previous threads... I added a crude Paint Brush illustration below…

**
The questions:
I have read that the AFM must be level in the car...
I thought this was only for the S4 "Door Type" AFM...
I have the S5 and it has the "Spring Loaded Cone" style AFM...
Does my AFM have to be level, and would this be the cause of the problems?
Does anyone have any other suggestions that would help?
**
I hope I simplified this long drawn out thread and I thank anyone who is able to help…

 

Please... Does no one know the answer to this question? Did I ask wrong or what? What do I have to do to get an answer around here...? Ask if I have enough air in my tire? I am sure that would be a "sticky" thread... I just need to know if the spring load cone MAF has to be level and I need to know if there would be any other things to look at that would cause the following four problems...

Hard start on a steep driveway...
Goofy idle when coming to a stop but smoothe when stopped completely...
Bucking when coasting at idle...
and
The Occasional back fire when I releaase the throttle at high RPM's...

Again... I ask please... Answer if you know something... I thank you in advance...

 

Wow, let's try a little patience here. This is a volunteer site. You know, like no one is getting paid to help you. Those who think they can help usually chime in when they read a post. It sometimes takes time for the right person to read a post.

Do some experimenting to determine if the AFM angle is your problem. Like return the AFM to a level position and see if your problems disappear. Also, you might want to check for air leaks in your intake setup.

 

The engine will start with the AFM in the back bedroom. The AFM has zippity doo dah to do with STARTING the car.

Now keeping it running, yes, you need a AFM and if series four, preferably level.

https://www.rx7club.com/forum/attach...hmentid=150447

https://www.rx7club.com/forum/attach...hmentid=150448

 

he has an s5 afm. i doubt it's the problem, but it could be more than one thing.

have you checked your tps? I say that because of the backfiring and bad idle

 

Ok.

What are you most concerned about? The car being hard to start or??? IF it's about just the start procedure, read my first post.

OR, just undo your angled afm and put it back as stock and see how the car runs then compared to now. Not talking about the hard to start, but the other symptoms.

Backfires when releasing the pedal. When you let off the pedal the fuel injectors stop feeding.......until you reapply foot pressure or the rpms drop down below somthing like 1100 rpm (I forget exactly). Part of that is TPS related.

Also there's an antiafterburn valve inside the ACV that injects a bit of air into the intake manifold to reduce afterburn. It does that when you let off the throttle and there's high vacuum in the intake.

 

First and foremost... I would like to apologize... I was pissed at the situation and I vented it here... That is not an excuse nor does it make it alright for me to act like a bitch... So again... I apologize for my previous nagging...

Second... I thank you all for the help... I beleive the funky idle to be a vacuum issue... I had a crimped vac line a while back that was coming off of the PCV... I made it long so that it would not crimp and it fixed the issue for a while... I got my wife to idle the car up to 2000 rpm a little while ago and I saw the sam vac line collapse... I got some poyurethane tubing and shoved it in the middle of the vac line that was collapsing and shortend it... I put it back on and all was good for a while... Then it started doing it again...

I hate to say it but I think I may have to pull all of the silicone vac lines off that I spent 2 days putting on and go back to a better vac line... Those things dont stay on... They get hot and squishy... They just suck...

I will check the TPS for the backfire... I re-leveled the MAF... The car had a hard start issue once since I leveled the MAF... It was flooded I think... It was not flooded previously... It acted like there was no gas at all... I wil also locate the ACV and find out what I need to do to check it...

Again... You guys are awesome... My car would not be running at all if it werent for this site... I appologize again for the gripes... And thanks for all of the help...

I am going to breathe now...