Hard start!

Joined
10 March 2012
Messages
503
Location
New Bern, North Carolina
I have not had an issue with my NSX since I have owned it, but it is starting VERY hard. I'll turn the key and let everything get going and usually the first time I turn the key it will crank for about half a second and then stop. There is no sound after that. Then when I release and go to crank it again, it will crank for a while and then turn over. My first thought was the main relay. I pulled it and re-soldered it and there was no improvement. It sounds electrical, but I can't think of what else it may be. Weak batter?

Thanks in advance for the advice. I love being about to use prime. The ultimate NSX owners resource.

-Alec
 
Hi Alec - just saw this - never had that issue like that with the car - and I did replace the Main Relay not too long before you got the car - so not sure what the issue might be. Hope it is something simple. Keep us posted. Jay
 
I assume when you say the engine will "turn over" you mean it will start running.
Do I also understand you can turn the starter on but it will stop on it's own?
If that's the case I'd remove the ignition switch and clean it out or replace it.

If its not the switch, I know this will sound simplistic but for ignition you need fuel, compression, and a spark.
Assuming you have decent compression then if your engine is hard starting I'd look to fuel and spark.
Is your fuel fresh? No water in there from winter condensation?
Spark plugs fresh? Coils in good shape?
 
I'll keep you posted Jay. It started a little after XPO and I didn't notice it much because I didn't drive it much after that, but now it is starting to drive me crazy. Ill have to check the ignition switch. That sounds like something else that could be the cause. I know it isn't fuel or spark because it happens before the engine gets turning. I may take a look at the started also. Are there any common issues with a starter solenoid?

-Alec
 
VancouverBCnsx was having similar problems so he may chime in or you could do a search with his handle and see the thread he had on it.
 
It sounds pretty similar to the issue I was experiencing with my 91 NSX. I ended up replacing the starter motor to resolve the issue. I believe that you can buy a kit to refurbish the contacts in the starter solenoid if you don't want to replace the entire starter motor. However the cost differential wasn't large enough to motivate me to mess with the original starter. In my case once the car was started and warmed up, a subsequent restart shortly thereafter was often quite normal. I wonder if you have noted the same thing.
If the issue is not related to the starter, a faulty ignition switch is probably the source of the problem.
Good luck.
 
I'm having a similar problem. Car takes 3 or 4 attempts to start and then finally catches. I think it's the fuel pump relay though as I can hear something clicking behind my head. I just replaced the main relay 2 days ago thinking it was that. I've ordered a new fuel pump relay, let's hope that does it.
 
You can bypass the fuel-pump-resistor relay with a couple male quick connects and a short piece of wire. That will eliminate the relay and the fuel pump resistor as potential problems, leaving the pump itself as a candidate.
 
Guys,

This does not really sound like a fuel problem (relays). Sure sounds like the starter needs rebuilding, or ignition switch. JMO...

Regards,
LarryB
 
My "symptoms" seem to change. Yesterday I had a hot start and everything was cranking well, engine just wouldn't catch. Finally on the 5th try it started after cranking for 3-4 seconds. In the morning, it started out with turning the key, noise for maybe half a second, and then either nothing or tons of clicking behind me. I should have my fuel relay today or tomorrow, so I'll try it since it's cheap and easy to fix. If that doesn't work it's starter time I guess.

Edit: After sitting all day while I was at work, it started up perfectly just now. Very weird. Relay should be here tomorrow so we'll see what happens then.
 
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Sounds like the starter on earlier yrs nsx starting to slowly fail. I notice my 93 would required 2 full crank to catch and run. Even on a brand new battery. It started right after i installed the stock bored throttle body. I am also running 6lb ctsc. But was fine before bored tb. Related? I dont know.
 
I seem to have a similar problem this morning, and any advice would be appreciated:
Car was driven about 200 miles just 5 days ago, and everything seemed fine, until I tried to start this morning.

1st start: engine cranks, sounds normal for 0.5secs, peaks at ~700rpm, then immediately dies
2nd start: same as 1st start
3rd start: apply a little throttle, engine cranks, I hear an exhaust pop (flooded engine with fuel?), then immediately dies

'92, manual trans, 300k+ miles, no engine mods. Any thoughts?
I hope it's not retirement home time :(
 
Fuel pump, maybe? Getting old and worn out, perhaps. That's quite an amount of mileage.
 
I switched out my battery and it stopped my cars hard start problem for a while, but it is back again. I didn't think it could have been the battery at first because the battery checked out ok but I swapped it anyway.

Now I'll go to start it and it will start right away and stall right away. I start it again and it runs just fine. It isn't all the time, but probably one in 10. I think I'll start digging into the fuel system and see if something is wrong there.

-Alec
 
Does you car sit for long periods of time?

My starting issues returned after I stopped driving my car daily. I replaced the battery and it now stays on a CTEK charger. No issues since.


I switched out my battery and it stopped my cars hard start problem for a while, but it is back again. I didn't think it could have been the battery at first because the battery checked out ok but I swapped it anyway.

Now I'll go to start it and it will start right away and stall right away. I start it again and it runs just fine. It isn't all the time, but probably one in 10. I think I'll start digging into the fuel system and see if something is wrong there.

-Alec
 
I keep mine on a trickle charger/battery tender if it sits for more than a week, but I typically drive it once or twice a week. Last winter when I tore it all apart I didn't drive it for months and the combined with the cold is what finished off my battery I think. This new issue is weird though. Almost seems like a vacuum line or something isn't connected or something isn't reading right.

-Alec
 
Here's a video of the 2nd attempt at starting. This is after waiting 60mins after the first start, with the battery on the charger the whole time.
https://youtu.be/s1gmfkHx9jw

I'm suspecting fuel pump issues, like you said. Is that a complicated replacement?
I'll double check the battery as well, but it's been on a tender ever since.
 
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good luck,i'm impressed by how many miles you have on your car. Where in nc are you?
 
My issues have been resolved once again. I was having a bunch of VERY hard starts with my dash lights flickering and was super worried. Then the car wouldn't start at all. I could hear the main relay could hear the fuel pump and all my fuses were good. Decided to check the ignition switch before I looked at the starter. Turns out I just had a dirty ignition switch. I opened it up to see how bad off it was and it wasn't too bad. I cleaned it and now the car starts like it did 25 years ago!

-Alec
 
Here's a video of the 2nd attempt at starting. This is after waiting 60mins after the first start, with the battery on the charger the whole time.
https://youtu.be/s1gmfkHx9jw

I'm suspecting fuel pump issues, like you said. Is that a complicated replacement?
I'll double check the battery as well, but it's been on a tender ever since.

Check out the system voltage during your start attempt. Its dying - looks like it was heading south of 8 volts.

Your battery could have 1 or more dead cells; however, before replacing your battery I suggest you check the clamps on the battery posts. There is a good chance that they are loose and or corroded. If they are loose, it is likely because they have been over tightened and stretched. That is a very common problem with the light weight clamps that Honda uses. If they are stretched, you can buy battery post shims which can be a fix, or you can re terminate the cables with new clamps or, at least for the ground cable, you could buy that heavy duty ground cable that somebody is offering.

Edit:

The audio wasn't working the first time I watched your video (computer was connected to an external audio mixer). I watched it again with the audio enabled - the engine cranks over just fine. You don't have a problem with the battery cables. The problem is somewhere else.
 
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out of interest when was the last time you changed the fuel filter?

reason i ask was that i had a similar starting issue (not as bad, just took longer cranking before it fired up) and the fuel filter was the original one, swapped that out and it went away :)
 
out of interest when was the last time you changed the fuel filter?

reason i ask was that i had a similar starting issue (not as bad, just took longer cranking before it fired up) and the fuel filter was the original one, swapped that out and it went away :)

I agree that the fuel filter is a possible candidate. The popping during restart could be gas exploding in the header due to a grossly rich fuel mixture; but, it could also be lean misfire or gas exploding in the header because the mix was too lean to ignite in the cylinder. However. before changing the fuel filter, I suggest a fuel pressure check. If you are not making rated fuel rail pressure, then replacing the fuel filter would be a logical next step. If that does not solve the low fuel pressure problem, then its likely a failing fuel pump. If the fuel rail pressure is within spec, then your starting problem is somewhere else.

As a note, if the fuel rail pressure is low enough to cause starting problems, I would expect that the car would have a lean running issue when the car was under load. This would normally cause the ECU to generate a fuel mix out of range error code because the ECU would likely have trouble bringing the AFR to stoich when the ECU was in closed loop. Did any MIL codes appear before this problem emerged?
 
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out of interest when was the last time you changed the fuel filter?

I've owned the car for about 12k miles, and haven't changed it yet

I agree that the fuel filter is a possible candidate. The popping during restart could be gas exploding in the header due to a grossly rich fuel mixture; but, it could also be lean misfire or gas exploding in the header because the mix was too lean to ignite in the cylinder. However. before changing the fuel filter, I suggest a fuel pressure check. If you are not making rated fuel rail pressure, then replacing the fuel filter would be a logical next step. If that does not solve the low fuel pressure problem, then its likely a failing fuel pump. If the fuel rail pressure is within spec, then your starting problem is somewhere else.

Thanks for the replies.
Ok, I'll check the fuel pressure. I'm not located with the car at the moment, but will make a trip back to the NSX this weekend. Just ordered a fuel filter just in case, because if I don't fix the problem this weekend, I'll have to tow it to GA.
Anyone know any good techs/shops in GA, near Atlanta?
 
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