Jump to content
SAU Community

Rb20det Starting Issues

niclol

By niclol,
in General Maintenance

 Share

Recommended Posts

niclol Enthusiast

niclol

Posted
Posted

Hi all

I'm having an issue with my silver top RB20 intermittently not starting properly. If I turn the car on and it's dead cold it starts but if I turn it off straight away and try to start it again it sometimes wont start or even sound like it's close to starting. For it to start again it needs to left for several hours it seems.

The car has been sitting for the last 6 months however prior to that I've had no trouble with it starting in my 5 years of ownership.

At one point when it wasn't starting it ran out of fuel I think (dodgy fuel gauge) as the pump started making a loud noise. I've since filled it up so the fuel in it should all be fresh.

I also had an issue with the car running badly above 2000 rpm and swapped to a new AFM however this hasn't changed the starting issue at all.

If anyone has any suggestions that would be great as I'm at a real loss at what to do :(

Link to comment
https://www.sau.com.au/forums/topic/453454-rb20det-starting-issues/
Share on other sites
Dose Pipe Sutututu Grand Master

Dose Pipe Sutututu

Posted
Posted

When this happens, try and unplug your water temp sensor on the coolant neck. It's the 2x wire one that goes to the ECU, see if that helps or unplug the AFM

It could be when your car is warm/warmer the cranking enrichment isn't enough to get the motor going.. it could be a mixture of things, dirty/faulty AFM, faulty FPR, dirty injectors, etc.

niclol Enthusiast

niclol

Posted
  • Author
Posted

Changed the spark plugs today, while the car seems to run smoother now it didn't change the starting issue :(

I tired unplugging the wire on the coolant neck while it wasn't starting but that didn't make a difference.

I should mention that I've been turning the car on for max 30 seconds before turning it off and trying to start it so I don't think the problem is really heat related. That said if you leave it for a few hours and come back it will start first time.

How would a go about testing the fuel pump? And could that cause an issue with just start up?

Dose Pipe Sutututu Grand Master

Dose Pipe Sutututu

Posted
Posted

Changed the spark plugs today, while the car seems to run smoother now it didn't change the starting issue :(

I tired unplugging the wire on the coolant neck while it wasn't starting but that didn't make a difference.

I should mention that I've been turning the car on for max 30 seconds before turning it off and trying to start it so I don't think the problem is really heat related. That said if you leave it for a few hours and come back it will start first time.

How would a go about testing the fuel pump? And could that cause an issue with just start up?

did you disconnect the coolant sensor for the ECU or the one for the dash? the ECU one has 2-wires not 1...

Dose Pipe Sutututu Grand Master

Dose Pipe Sutututu

Posted
Posted

(not sure how related this is to you but here goes)

do you have access to a wideband o2?

back in the days when I knew nothing about cars (10+ yrs ago).. I had the same issue with my RB20DET, a mate that was doing engineering at uni suggested I hooked up his wideband. Ended up finding out the car was running lean in general when it was in vacuum, turned out my injectors were all clogged.

As soon as got all the injectors serviced, new o-rings put in the car started easily and idle was back to stoich.

Sinista32 Grand Master

Sinista32

Posted
Posted (edited)

Humour me a little and just try a mates battery

Don't use a jump pack or try jump it off another car

Connect direct to terminals

Ps. Every time you try to start it and it doesn't start your plugs get a bit dirtier and eventually fouled again.

Edited by Sinista32
niclol Enthusiast

niclol

Posted
  • Author
Posted

Just tried a battery out of a car that gets driven every day, had slightly higher cca as well. Result was still the same though.

While it wasn't starting I also took the line off the fuel filter and primed the car and tons of fuel came out. I don't know know if that tells me if the pump is working fine though.

  • 2 weeks later...

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing


  • Similar Content

  • Latest Posts

    • Matt Z
      SAU NSW - Chickos Cruise

      By Matt Z · Posted

      Scenic roads, stunning skylines, and Chickos to finish it off! Join SAU NSW as we cruise through the Royal National Park and along Lawrence Hargrave Drive to Figtree! Sunday 26th October 2025 4:30PM Meeting Waterfall Station Parking 5:00PM Cruise Departure Royal National Park > Lawrence Hargrave Dr > Memorial Dr > Sid Parrish Park 6:15PM Arrival at Sid Parrish Park Figtree Meet Location: Waterfall Station Parking Final Destination: Sid Parrish Park RSVP: https://forms.gle/E4s5SiRKQfDdypky8 *Disclaimer* There will be a lead and follow car so no one should get lost. If you would like to attend or bring others along please put your name down and a +1 as numbers will be needed prior! This is NOT a race and we will all be adhering to all road rules. If this is what you want please come to one of our many track days. This is an official SAU:NSW event and will be run under a CAMS permit. One of the things that really sets our club apart is our commitment to being true enthusiasts. When on normal roads we strive to maintain good relations with the authorities as well as the public in general. When attending one of Skylines Australia NSW events please try to: • Be aware of surrounding environment and act accordingly. • Drive courteously on the state’s roads as a true enthusiast should. • Understand how important it is to maintain the good name of SAU NSW and thus, treat others accordingly. • Any misbehavior will not be tolerated and you will be asked to leave.
    • MBS206
      "Cheap" bolt on turbo on RB25DET NEO

      By MBS206 · Posted

      It's funny, as Ive seen plenty of people use them in cheap builds on YT. And they actually go okay, even though a lot of other maxspeedingrods stuff is terrible. Those turbos seem reliable enough, the only part being, a good quality turbo that is "identical" to it, will out perform it day in and day out. In both a lower boost threshold, and the ability to flow more air at the same boost pressure. As a cheap cheap replacement, not a terrible choice. For cheap and shouldn't blow in a day, not terrible (like other eBay/Temu turbos) for low cost and still decent performance, that's where the question comes in to play from the results I've seen. I'd actually find it hilarious to buy one, and strap it to a paddock basher or some other cheap as POS originally NA car, and send it to the moon!
    • tylink720
      "Cheap" bolt on turbo on RB25DET NEO

      By tylink720 · Posted

      The maxpeedingrods turbo is cheap and bolts on to stock parts. I think you just need a bigger silicone coupler for the intake. Its a cheap china turbo, but it's been running on mine for almost 3 years at 16-19 psi.
    • MBS206
      Strange issue RB25DET wont start

      By MBS206 · Posted

      What do they look like right after you've tried to start it with everything connected? Also post photos of what they actually look like.
    • jtha7
      Strange issue RB25DET wont start

      By jtha7 · Posted

      Also wanted to say, my new spark plugs are blackened looks like it's very rich. I have splitfire coilpacks but stock coilpack loom and ignitor. I tried directly grounding the ignitor ground to body as well. 
×
×
  • Create New...