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wopa20 07-08-23 02:10 PM

Ok so I’m getting gas from that pipe, I’m pretty sure the pump is working as it should. I can get the car to fire but she stalls shortly after. I’m leaning right now to fuel pump relay and mass air sensor. I’ve checked manuals about testing fuel relay but if looks different from mine. I believe mine is mounted directly behind passenger headlight. It has four prongs after I unplug. The manual shows 5 plug
https://cimg7.ibsrv.net/gimg/www.rx7...9f6c14d7f.jpeg

WondrousBread 07-08-23 02:21 PM

The relay you're looking at behind the headlight is probably the Air Bypass Relay. The fuel-pump relay (Mazda lingo for it is "circuit opening relay") is mounted to the steering column, and is the six pin relay pictured there.

I would check and make sure the MAF is plugged in, and also the green connector I mentioned way back on page one. Either one being unplugged or bad can cause this symptom.

wopa20 07-08-23 04:22 PM

Ok green sensor and maf is plugged in, maybe the maf sensor is not working…. It was seized shut at the beginning. Possibly damaged trying to get it moving. Will bench test again

rlynchster 07-10-23 08:34 PM

Do the flapper fuel pump trick. . . ..With the key in second position prior to start, if you push on the flapper in the MAF with your finger, you should hear the fuel pump kick on. . It is easier to do this with the air box off to get access to the flapper, but I think you could push something in there with the filter removed. .Mine does and it's 86 N/A 4 lug.. . . .

WondrousBread 07-11-23 10:28 AM


Originally Posted by rlynchster (Post 12567542)
Do the flapper fuel pump trick. . . ..With the key in second position prior to start, if you push on the flapper in the MAF with your finger, you should hear the fuel pump kick on. . It is easier to do this with the air box off to get access to the flapper, but I think you could push something in there with the filter removed. .Mine does and it's 86 N/A 4 lug.. . . .

This is a good idea because it tests the switch inside the MAF. The yellow test connector shows that the fuel pump and COR are working, so this will take the last element out of the equation.

It won't test the MAF reading itself though. For that you need a multimeter.

wopa20 07-11-23 09:25 PM

Shoot, wish I saw this post earlier. I just order a remanufactured maf from rock auto. $100 didn’t seem bad at all. Another Thing I noticed was when the car stalled the air control was clicking like crazy. I tested by powering when I had the intake off and it clicked so I thought it would be good.

WondrousBread 07-12-23 05:12 AM

That air bypass relay controls the big air solenoid (it has a real name, and I don't recall what it is) on the intake. It's the big cylindrical thing behind and under the BAC, with a two pin plug.

It shouldn't really matter for starting. Having it disconnected just defeats the 17 second 3000rpm startup function, which IMO is a good thing.

EDIT: Although it clicking rapidly sounds odd. Relays don't usually fail that way. I would probably ignore it for now.

wopa20 08-06-23 09:27 PM

Got the rebuilt maf and installed. Car is still doing the same thing. Start for a second then stall then hard to get started again. Any ideas where to go next?

rlynchster 08-06-23 10:23 PM

Go with the starting fluid. . .. . Spray some in the intake during startup. If the car seems to want to run longer, it would point to excess air from somewhere. . . Below are some things that I would look at in such a condition.

If you don't have your EGR blanked off, you should do that.. . Requires UIM Upper Intake Manifold removal.

Make sure the vacuum spider (plastic 4 into 1) adapter is not cracked and broken. .. .. May require UIM removal.

Double check to make sure the seal between the intake snorkle and the top intake manifold (UIM) is not leaking.. . Make sure the o-ring is there and sealing.

Ohm out the BACV to the FSM

Change the water temp Sensor under the alternator. backside.. . Requires alternator removal to be easier to get to.

Check your double throttle diaphragm vacuum line all the way back to the block and make sure nothing is cracked or leaking.

Make sure the air adjustment screw is not fully in or out.. . Should be in the middle somewhere.

Check to make sure the boost sensor vacuum line is not cracked.

Change plugs./ wires

Back probe the Throttle Sensor and make sure you are adjusted to 1 volt.

https://cimg9.ibsrv.net/gimg/www.rx7...f24e9607d1.jpg







diabolical1 08-06-23 10:33 PM

it won't let you keep it lit with your foot?

diabolical1 08-08-23 07:57 PM

was reading another thread and it involved "clicking", so i thought of you. have you tried bypassing the pump relay? in the other thread, that's what it was (pump relay).

wopa20 08-12-23 12:37 PM


Originally Posted by diabolical1 (Post 12570902)
it won't let you keep it lit with your foot?

Gas pedal does nothing to keep it going. I touch it at all and it dies

wopa20 08-12-23 12:40 PM

Thanks for the good advice, will take a look at all of these when I return from vacation.

rlynchster 08-14-23 06:43 PM

Check the TPS first. . . .if it idles and dies the moment you give it gas, I would check the TPS.. . .Easy check. . .check its volts and resistance.

Terrh 08-23-23 10:46 AM

Any flapper AFM bosch type system like the FC has, if it starts fine but won't run the #1 thing that points to is the AFM not working - either not providing a signal or the door is binding or a massive air leak.

The ECU does not use the AFM for startup fueling, only for running fueling,

What part of Ontario are you in? If you're within 200KM of Windsor I could probably be talked into coming over and helping you get it running.

Fuel pump has to be working or it would never start. Can eliminate the entire ignition system as a cause of problems as well.

TPS - maybe - but even with a disconnected or stuck TPS it should still be willing to keep running at idle.

I'd look real hard for big leaks and then bench test the AFM. They're very simple and easy to test.

kingskwerly 08-25-23 04:19 AM

It nice to comeback from a real long time away and seeing other old members coming back. Can’t wait to see what you do

wopa20 11-14-23 11:34 AM

Had to take some time off but Ive found some time to return to the project. In the meanwhile, I did rebuild rear brake calipers and it seems my brakes are all working well. I have one suspension issue, I order energy bushings to replace links for stabilizer bars. When i grease these bushings and attempt to install them I find that it just pushes out the other side (quite annoying). Any tips of this? Also, I am now returning to getting car started. Just a recap, car starts, revs then fails and will not restart. I'm leaning towards the car flooding. As per prior suggestions I have replaced MAP and that green temp switch located behind alternator. I did a leak test and may have small leak (hard to tell). I did find that the TPS was set out at 2k so I adjusted back to 1K and 5.7k throttle open. Have not tried yet, bought some gas and will attempt after work. Fingers crossed!

wopa20 11-14-23 11:35 AM

where is pump relay?

wopa20 11-14-23 04:30 PM

1 Attachment(s)
Got it to fire! I think she was flooding. This is what I have now

wopa20 11-14-23 05:26 PM

I started it a few times. Wants to die but at least now I can rev her with the gas pedal. Had it up over 3000 rpm’s. If I lay off gas she crashes. I did notice that the exhaust is getting very hot and smoke started to come off of it. (This could be undercoating burning off from many years ago but hard to say.) I’m leaning towards timing issue?? I see marks but haven’t found how to set up yet.

wopa20 11-14-23 05:32 PM

Sorry for all the posts at once. Checked manual about timing and it states when car is running attach light. What if car can’t stay running?

wopa20 11-14-23 06:14 PM

Ok so I found video explaining static timing… pull angle sensor pulls at leading mark ( mark clockwise of second mark) reinstalled now she completely dosnt cooperate. No start

diabolical1 11-14-23 06:25 PM

rotate the engine around to the yellow mark and keep it inline with the pointer on the front cover (make sure the pointer is not bent).
pull the CAS.
line the little divot up with the tang/mark.
install the CAS.

this is where the engine should start.

if that doesn't work, then try to use the flywheel to verify the pulley.

wopa20 11-14-23 10:04 PM

I attempted to set timing a few times. I haven’t checked the flywheel yet. Feeling quite defeated

wopa20 11-15-23 08:06 AM

Was talking to older mechanic guy and he states that maybe I have the timing off 180 degrees. I have the mark on sprocket and on the distributer shaft lined up, not sure how something like that could happen. is it ok to mess around with this sensor?


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