So i got a 1986 rx7 it has a fuel injected 13b.So i get in the car start it. It runs but kinda sputters or seems like its bout to die but stays runny.here is the problem i can give gas and hold it the car revs and stays running but as soon as i let off it dies.and if i give it gas slow it dies.anybody have a clue how to fix it.

 

Can you please provide us with more information? Even some general engine bay pics may help us weed through this, especially if you're new to these cars and not familiar.

Has the car ever run fine in the time you've owned it?
What, if any mods are done?
What, if any maintenance has been done to the engine recently (and with proof!)?
Is the emissions system FULLY intact. If not, what is missing?
How have you already troubleshot this issue up to this point (if at all)?

Please, while waiting for answers/help download the factory service manual and start familiarizing yourself with some of the tune-up/maintenance procedures (we will surely ask you to check basic things such as timing/CAS stabbing). If you properly read all the new member info you will have come across a link in the stickies/FAQ to download this for free.

 

Info on his situation found in another thread:

https://www.rx7club.com/new-member-r...erate-1093784/

 

I bought the car used for 550 and i do see new wires and coilpacks and the questions it looks pretty stock as i can tell also i did see something odd with the thorrzle it is ziptied to a set level

 

While I don't think it was beneficial to have started this thread in addition to the other, I will say that this new information is giving you some clue that:
1. The emissions/idle control systems have most likely been tampered with or a small vacuum leak is present and wasn't identified.
2. The previous owner had no idea what they were doing.

Although many people on this forum blindly remove their emissions equipment, a stable idle is still possible when the person knows how the engine/idle works as a system and can set the few remaining sensors/adjustments accordingly. Same goes for a vacuum leak, it's not rocket science.

With that being said, I did not see a response to question number one in your original thread: what are the compression results?

 

I havent had a chance to buy the compression testee

 

I'm not sure if someone posted this in your thread, but a traditional piston compression checker needs to be modified to tell you anything, and even at that it's not very accurate. Most people just hold the bleed valve down and call it "good enough".

There is a method where you can pull the plugs and listen to the compression puffs. Please reference the "Poor Man's Compression Test":
http://www.rotaryresurrection.com/ro...lder/comp.html

More of similar information here:
http://www.racingbeat.com/mazda/perf...ion-check.html

 

Im going to try this once it stops raining im just so ready to drive my car

 

So i went and tries the car today i got it to drive in gear but it keeps hesitaing and seems like it wants to kill what can be the cause the car just wont stay statered

 

We are going to beat this horse to death. Step number one. COMPRESSION TEST!!!

Pending those results, if good, you will progress to basic things like verifying timing, spark, fuel/pressure, TPS and mixture adjustments, but none of them do any good if you don't verify you're starting with a good motor.

 

An effective response (lets hope it holds).