Cold start issue 4th gen jdm vtec - any suggestions?

Post by **DaveyBa8** » Mon Oct 31, 2016 9:26 pm

When you say 4-5 cranks do you mean turning it over, stopping and turning it over again?
Check your earths first before you do anything.

Post by **vanzep** » Tue Nov 01, 2016 12:11 am

Yep takes 4 goes at turning it over - it nearly fires up first time and with each go it improves - feels like it does actually fire up but then stalls and youve got to catch it with the accelerator.
Ive checked and cleaned the earths at the cambelt engine mount, earth to front slam panel and the main earth strap at the battery and starter - dont know if ive missed any....
The car does have a lot of electronics to get going on start up

Its the only issue with the car as absolutely everything works exactly as it should - just need to get this sorted

bennyboy · Post by **bennyboy** » Tue Nov 01, 2016 8:52 am

If it gets progressively better each time, could it be something like injector? I'm just thinking common sense, so as the fuel starts to come through, it cleans the gunk / obstruction, until it fires?

Post by **vanzep** » Tue Nov 01, 2016 9:17 am

Ive run some fuel line/injector cleaner through and it made a very slight improvement so ive sort of discounted that as being the issue. Having said that i did notice in the MOT history that it had been missing the fuel cap for one MOT and then had a temporary fuel cap fitted for the next MOT wonder if this has any bearing on the problem.
Im going to change the Coolant temp sensor today and see if that fixes it - fingers crossed

If not then i will have to look at the FPR and fuel pump.

Post by **JEBB4** » Tue Nov 01, 2016 9:29 am

Sounds like lack of fuel for some reason, I'd be thinking of removing the injectors and checking the filter baskets, sometimes no amount of fuel system can resurrect them if there too far gone..

On a simpler note just check the vacuum lines to the fuel pressure reg and also the little electronic vaccum control solenoid at the other end of that pipe as if the solenoid diaghfram has weekend may not be providing quite enough vaccum at first to the reg... Just a thought other than all the other suggestions above..

Post by **vanzep** » Tue Nov 01, 2016 5:26 pm

I changed the coolant temp sensor and will see if that does the trick - i will have to wait until tomorrow morning to test it from cold (will be below zero tonight-brrrrr)
here is a pic of the old sensor that i removed - it was fairly doused in oil looks like it may have been removed before as it has grey hondabond on the threads.

also checked the battery/alternator again.
still showing 12.5 with ignition off and 14.55 when running (no load).
so all is good there

JEBB4 wrote:Sounds like lack of fuel for some reason, I'd be thinking of removing the injectors and checking the filter baskets, sometimes no amount of fuel system can resurrect them if there too far gone..

On a simpler note just check the vacuum lines to the fuel pressure reg and also the little electronic vaccum control solenoid at the other end of that pipe as if the solenoid diaghfram has weekend may not be providing quite enough vaccum at first to the reg... Just a thought other than all the other suggestions above..

ive checked the vaccum lines for leaks - all are ok as far as i can see
might have a look at the injectors if problem still exists tomorrow

Post by **DaveyBa8** » Tue Nov 01, 2016 6:41 pm

Sounds like fuel to me too then. Mmmm it's a strange one.

Post by **vanzep** » Wed Nov 02, 2016 1:52 pm

Well it started up a lot better today and was below zero last night so quite happy with that - i will have to test it out over the next few days and see if changing the coolant temp sensor has indeed fixed this issue. If not then i will have to look at fuel delivery side of things.
Thanks to all of your for your helpful suggestions

Post by **NafemanNathan** » Wed Nov 02, 2016 3:25 pm

vanzep wrote:also checked the battery/alternator again.
still showing 12.5 with ignition off and 14.55 when running (no load).
so all is good there

Is that just at the battery terminals? Have you tried a reading on the positive terminal and then around the earth straps on the block?

Post by **vanzep** » Thu Nov 03, 2016 3:39 pm

Fitting the new temp coolant sensor has improved it slightly but still doesnt start on the button like my BB4

I will check the earths again but i did check them all and clean them up when i did the clutch&flywheel a few months ago.
I guess most people wouldnt be bothered about it taking a few cranks to get going in the morning but for me its a mystery that must be solved