Weird starting issue

[dhen]

Happy Turkey Day

It's been cold here, so I haven't really been in the garage much. Anyway, here's the situation:

Battery was slowly dying. I went to the junkyard and got a different one. (Yeah, I know, but I need to save money.) The engine still cranks slowly and won't start but now the car makes a VERY loud backfire when I try to start it.

How is this possible? The engine ran great before the battery died. Usually a backfire means bad timing, but I haven't touched that. I read that if there isn't enough power for the spark plugs, this is possible. The battery was recently charge and at 12.6 volts.

[float_6969]

Volts don't mean isht. Amps is what turns the motor over. I'll bet you money that if you could datalog the voltage, it was drop WAY down when you crank it. I suppose it's possible the starter is taking a dump, but I'd start with a NEW battery before I replace the starter.

[dhen]

Thanks for the input. Could low amps cause the backfire? That's the weird part for me.

[float_6969]

Yea, if the battery can't supply enough amps, the volts drop. When the volts drop, you get poor ignition and the engine turns over slowly. These can cause a backfire.

[dhen]

OK. That gives me something to work with.

By the way, my engine is no longer haunted. I got one from Dee.

[boost_boy]

Ryan is right! It happens when you load the cylinders up with fuel when starting, but have a weak supply of ignition power (spark). No worries as it happens to me when I screw around with disabling and enabling the MSD DIS-2 on all of my CA powered cars. Each one of gives me a nice back-fire and then crank right up.

[dhen]

Good to know.

I got the battery tested at AutoZone and it tested bad, so that's proof that volts don't mean s***, since the voltage was great.

That's the second bad battery from the junkyard. It's a lot cheaper, but this is getting old. I may have to bite the bullet and buy a new battery. I mean, it's starting to be the same with the price of gas.

[dhen]

Well, I bought a new battery and it still didn't start. Pulled the starter and had it tested and it came out OK. Started swapping out spare ignition components and it turns out that my CAS was totally dead.

I guess that's why the car was running great and then suddenly crapped out. I was considerate of the car to die in my garage instead of somewhere else.

Always good to have spares. Off to PickNPull to get another CAS. I believe the KA ones work.

[float_6969]

The KA doesn't have a CAS. Well it does, but it's built into the distributor. The only CAS that will work is one from a DOHC CA (either the 1.6 or the 1.8)

[cadet18]

ive got a somewhat similar issue still ongoing where when i turn the key it will click like the starter is going out i turn the key a few times and it will finally spin. once it starts it will run for a few seconds then cut off. after a few starts and playing with the gas pedal it will eventually stay running.... this happens hot or cold. im not wondering if my starter could be causing this as well, as i have a new battery. when i get back home in a few days ill have to check voltage as well. sorry if this seems like a thread jack just thought id share my somewhat similar issue as well.

[dhen]

My car fires up perfectly now. I actually don't know if the original battery was bad. I just assumed it was because it was old. My CAS was definitely bad.

[float_6969]

ive got a somewhat similar issue still ongoing where when i turn the key it will click like the starter is going out i turn the key a few times and it will finally spin. once it starts it will run for a few seconds then cut off. after a few starts and playing with the gas pedal it will eventually stay running.... this happens hot or cold. im not wondering if my starter could be causing this as well, as i have a new battery. when i get back home in a few days ill have to check voltage as well. sorry if this seems like a thread jack just thought id share my somewhat similar issue as well.

Sounds like a bad starter.

[omgws]

Hello. i just bought an nissan 200sx ca18det, it worked for 2 days. and after i filled 98 octane it wouldnt run properly, the next day it was hard to start but came eventually and i drove to work and after work it wouldnt start.

it tryed starting it for 5 min and it would only run for a few seconds before it died again and wouldnt start. ( not sure if it was 2 or 4 sylinders)
and i tryed again the same happened but this time it only ran on 2 sylinders.
tryed swapping to another ecu but wouldnt work. (ok)
and then we checked if there was any blockage after the fuel filter. (ok)
we also checked the ngk iridium spark plugs (ok)
tryed switching the cas (ok)
before i installed the other cas i checked if the fuel injectors supplied fuel. (ok)
ckecked all the grounds from the battery to the engine block(OK)
checked the wiring from the coils to the first connection (where the 4 coil plugs go into 1 ok)

Please help me would really appreciate any answer, ive been working on it for 2 straight days now and could really use the help

Best Regards oli

[omgws]

Just found out it's the wiring (i think) so im going through all the wiring form the engine bay to ecu.

will post if i find out the problem

Best Regards oli

[omgws]

wiring harness*

[omgws]

was also wondering how do i measure the ohms on the coils?

Best Regards