Have to crank a long time for engine to start when cold.

dabes
Club4AG Regular
Posts: 22
Joined: Wed Aug 07, 2013 11:06 am

Have to crank a long time for engine to start when cold.

Postby dabes » Thu Jun 08, 2017 10:11 am

I recently brought my 86 back to life. It is a 16v with USDM harness.

I just swapped the fuel pump out with a delphi unit from Autozone, becasue my old pump had died.

It ran fine for a short while, but then all of a sudden, I am running to an issue where I would have to crank for a good 10-15 seconds and the motor slowly cranks to life. Once it is warm, it will crank up just fine.

I have scoured this forum as well as other outlets and am guessing it could be a few possible issues, but I figured I should diagnose the issue before I start replacing random stuff on my car.
- I read somewhere that the fuel damper can make a significant difference in this.
- Could be the fuel filter
- Maybe the cold start? but then I havent heard anyone speak specifically about my issue.

Another maybe important detail is that the car had been sitting for about 3 years. and the gas in there was very old. I did refill it once I got it running again, but this was the reason why I thought maybe it could be my fuel filter.

Can anyone tell me what I should look into or any tests I should perform to get this worked out.

Thanks

dabes
Club4AG Regular
Posts: 22
Joined: Wed Aug 07, 2013 11:06 am

Re: Have to crank a long time for engine to start when cold.

Postby dabes » Thu Jun 08, 2017 12:47 pm

Just a quick update. I found out that my injector resistor is a little frayed. I dont know if this would cause this issue though...

CloudStrife
Club4AG Pro
Posts: 644
Joined: Thu Oct 06, 2016 2:23 pm
Location: Middle of Hell, Florida

Re: Have to crank a long time for engine to start when cold.

Postby CloudStrife » Thu Jun 08, 2017 2:22 pm

I'd recommend using the AE86 service manual for troubleshooting. It can lead you down a more organized path for troubleshooting other than just randomly guessing; it would help you out greatly.

If you don't already have it, you can download them here:http://www.aeu86.org/technical/ae86-manuals/

*These manuals are broken up by either being engine related or everything else.

Good luck!
Success guardian... Successsssssss..

User avatar
jondee86
Moderator
Posts: 2907
Joined: Fri Jan 11, 2013 10:21 pm
Location: Wellington, New Zealand

Re: Have to crank a long time for engine to start when cold.

Postby jondee86 » Thu Jun 08, 2017 4:09 pm

Sounds like maybe the cold start injector is not working. Easy to check... just
pull the injector out of the intake manifold and put the end down the neck of a
glass bottle. You hold the bottle and get someone else to crank the engine. If
you don't see fuel squirting into the bottle (only happens while cranking) then
either the cold start injector time switch is unplugged/borked or the injector
is blocked.

Cheers... jondee86
The reasonable man adapts himself to the world; the unreasonable one
persists in trying to adapt the world to himself. Therefore, all progress
depends on the unreasonable man.

davew7
Club4AG Expert
Posts: 232
Joined: Fri Jun 06, 2014 4:34 am
Location: Michigan

Re: Have to crank a long time for engine to start when cold.

Postby davew7 » Fri Jun 09, 2017 5:26 am

There is a cold start temperature sensor on the coolant neck that could be a problem. Verify that the cold start injector is getting an electrical signal. Dave W

Toy86
Club4AG Enthusiast
Posts: 63
Joined: Mon Jan 14, 2013 10:19 pm
Location: Tucson, AZ

Re: Have to crank a long time for engine to start when cold.

Postby Toy86 » Fri Jun 09, 2017 1:46 pm

Here's something you should check. You do have a fuel filter in your gas tank doesn't matter if it's GTS or SR5, check to see if that's clogged. You could also have a small crack in the line some where allowing air to get into ur lines making you loose your prime. That's why it fires back up once the lines are fully primed. Let us know what you find out. Good luck!

Toy86

dabes
Club4AG Regular
Posts: 22
Joined: Wed Aug 07, 2013 11:06 am

Re: Have to crank a long time for engine to start when cold.

Postby dabes » Sat Jun 10, 2017 11:24 am

thank you guys for all the information.

Its really random but it all of a sudden fixed itself today. I started up the car three times throughout the day. So odd.

taroroot
Club4AG Enthusiast
Posts: 103
Joined: Mon Jan 14, 2013 10:04 pm

Re: Have to crank a long time for engine to start when cold.

Postby taroroot » Sat Jun 10, 2017 11:35 am

Your fuel pump died? Did you change the fuel filter too? 3 year old fuel is pretty certain to be bad and gummy. Change and clean what you can. You might consider sending your injectors to a cleaning and testing service, they'll be able to quantifiably tell you if they are clogged. The services are quite fast too, they usually turn around in a day or two. The injectors in my 20v swap were quite clogged. Really should have checked my pump sooner. Had engine smoothness issues, then pump got noisy. Pulled the pump out to find the mesh of the strainer was gone! Hopefully there still isn't bits stuck somewhere in the lines. Will prob do another filter change soon just in case.