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-   -   Project "I have no clue what direction to go" (https://www.rx7club.com/new-member-rx-7-technical-256/project-i-have-no-clue-what-direction-go-1133517/)

pcody321 02-07-19 08:56 AM

Project "I have no clue what direction to go"
 
Ok so i have recently picked up this 1993 Fd. It is a one (now two) owner car owned by a old couple (it was bought by the couple for the his car and a mx-5 miata was purchased for the her car at the same time) he put very few miles on it and mostly drove it on road trips. It now had 25k miles and I have documentation from a service in 2001(I also have all of the service history) and it had 20k then. He parking it in about 2014 when he drove it and the motor made a pop noise and ran like crap so he stopped driving it. That's what I went in knowing. When i got in in to my shop and started working I was pulling the plughts to pour atf in the rotors and I noticed that one of the plugs was cracked (the metal end pulled out of the ceramic) so I can hopeful attribute the running like crap to that plug not firing. The motor is freenafter doing the atf and I tested the compression on both rotors and I had 123 & 125psi so that is great and I bought new plugs and checked for spark and I have spark so all i'm missing fuel. I replaced the fuel pump because the old one wasnt priming and now i have positive fuel pressure at the rail however the the injectors aren't pulsing... and that's where I am now
https://cimg3.ibsrv.net/gimg/www.rx7...9e2270b71c.jpg
https://cimg5.ibsrv.net/gimg/www.rx7...19593ade80.jpg
this in in the previous owner driveway
https://cimg6.ibsrv.net/gimg/www.rx7...fd196d719d.jpg
the odo looks bad but it had 25k
https://cimg9.ibsrv.net/gimg/www.rx7...6a72a1584b.jpg
Ive never seen an rx7 with seats that clean
https://cimg1.ibsrv.net/gimg/www.rx7...817984ad88.jpg
First night that I got it home and started working

Pete_89T2 02-07-19 10:00 AM

Given how long it sat unused with stale fuel in the fuel rails (since 2014?, yikes!), first thing I'd do is pull out all of the FI's and have them properly serviced (or replaced with new ones). Those old FIs are most likely gummed up pretty bad by the old stale fuel, so when you try to start the car the sticky FIs will either flood it or starve it of fuel. You should replace the fuel filter too.
While you're at it, it will need lots of TLC maintenance work while you're in there - i.e., replace all the old vacuum hose with silicone hose (reliability improvement), and it would be smart to replace all the rubber fuel lines as well.

You might also have an electrical issue with the FI wiring that could prevent them from firing, but that is less likely.

Nice find BTW - this one should clean up nicely!

WobblyBobbly 02-07-19 03:10 PM

Great find! +1 on the fuel system...better to find and replace those injectors and suspect everything else at the same time. When in doubt, throw it out if it's been sitting with fuel in it.

BLUE TII 02-07-19 03:23 PM

I would just change out the fuel filter, drain the tank, put fresh fuel in and verify it runs well.

Once that was sorted I would pull the engine/trans and gently clean up the engine bay and engine peripherals. Toothbrush and light oil for the corroded aluminum.

Put the engine back in, get it running and start to work on restoring the paint/body.

Alternately, you could just gently start cleaning what ever you can get to in the engine bay and by taking off and cleaning peripherals if you just plan on enjoying the car as a driver and putting miles on it.

Mangiavelox 02-07-19 03:33 PM

check your plug wire too, on my car with a engine freshly rebuilt one was broked and the engine would run badly. all hoses need to be check because with the years the rubber can dry and crack

Brandnewused 02-09-19 01:01 PM

Have you checked to make sure the injectors are getting a voltage signal to open, or checked the resistance to make sure the are any good? Hope this helps, I am sure you could find the numbers somewhere on this site. Also how much fuel pressure do you have at the rail?

LowandSlowDC5 02-10-19 07:41 PM

BLUE TII is pretty much spot on. Drain the tank, new fuel, spark plugs, and ensure your injectors are working correctly. I'd probably do the fuel filter as well.

AshyXElbows 02-11-19 12:39 PM

sounds like you're gonna come up on a great deal just needs a little elbow grease. worst case just pull it out and bridgeport it lol

pcody321 02-11-19 12:45 PM

the previous owner drained the tank when he parked it so i'm not worried about stale fuel and the injectors will pulse when i put 12v to them. it has new plugs and fresh 93 fuel

Pete_89T2 02-11-19 06:08 PM


Originally Posted by pcody321 (Post 12329570)
the previous owner drained the tank when he parked it so i'm not worried about stale fuel and the injectors will pulse when i put 12v to them. it has new plugs and fresh 93 fuel

It's good that the tank was drained and that the FIs click when you put 12V on them, but I'd still get them cleaned & flow tested. Doesn't take much fuel sitting in the rails & injectors themselves to gum up the FIs over several years. I've had good results with these guys: https://injector-rehab.com/shop/injector-cleaning/

AshyXElbows 02-11-19 06:12 PM


Originally Posted by Pete_89T2 (Post 12329641)
It's good that the tank was drained and that the FIs click when you put 12V on them, but I'd still get them cleaned & flow tested. Doesn't take much fuel sitting in the rails & injectors themselves to gum up the FIs over several years. I've had good results with these guys: https://injector-rehab.com/shop/injector-cleaning/

Yea for real, its not very expensive to do and helps for piece of mind

Akagis_white_comet 02-27-19 11:42 AM

I also recommend injector rehab, having used their services on my 20B-REW. That would be the first thing that I would do. Next I would disassemble the turbo control system (solenoid rack, underneath the upper intake manifold), test each solenoid and valve (see Dale Clark's threads), then reassemble with silicone vacuum hose.

At this time, you may wish to go simplified sequential as well.

Sgtblue 02-27-19 12:21 PM

—-> https://www.rx7club.com/3rd-generati...eaning-886616/

If you’re going in that deep replace the fuel pulsation dampener. Old ones have been known to leak and cause fires.

pcody321 05-03-19 08:33 AM

Ok so I'm sorry I haven't been active for a while but I was wondering if there was any way to check at the ecu for power going to the injectors to see if the wiring could be bad. I have also decided to pull the intake again to get out the fi's to send them out for cleaning and testing.

Sgtblue 05-03-19 10:00 AM

:dunno: , maybe I'm missing something...I've never had this issue. But if you're pulling the injectors, could you just check for signal right at the connector? And you really only need to check the primary injectors as the secondary injectors wouldn't keep it from starting and would throw a code anyway.

pcody321 05-06-19 08:34 AM

I was going to check at the ecu just incase the wire was pinched or something going to the injector, however i will only do that if after i pull the primaries and check I don't get signal. I keep forgetting but i need to figure out how to run the codes with the diagnostic box because the light is on.

Sgtblue 05-06-19 08:51 AM

——> Check Engine Light Codes


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