hot start issue

[Stott69]

Hey guys. Cars having an issue with starting when hot. Will turn over but not fire. Have checked and can hear fuel pump running. Starts from cold fine and will run for hours, but as soon as you stop and turn the car off it wont fire back up. Let it cool and its fine again. 
Where should I start?

[jbod]

What car and engine is it? Any reason you think why it may be starting to be like this? Ie potentially worn, low compression?

[Stott69]

Toyota Aristo. 255000km on the clock, so worn something, but not sure what? Im hoping its electrical and a easy/cheap fix as dont realy want to do a refresh for a year.

[strx7]

turbo or not?

[allencr]

Tried it with the throttle half way down?
Injectors dribble a little from residual pressure, more air helps starting up with that extra fuel.

[Stott69]

Yes running 10psi, stock ecu & injectors.
Yes have tryed pushing the gas pedal but to no help

[jbod]

Well hopfully electrical, maybe check the basics like compression if you feel the engine is gettin tired. Do you have a workshop manual for the aristo? From my experience its often little help people firing off it could be this and that; best to work your way through the manual troubleshooting section so you can rule out components one by one

[strx7]

if you turn the key on for 5 seconds then off, then on for 5 seconds, do this a few times then try starting it, what happens?

[Shrike]

I had a similar issue in my R32 with a Rb25 running the rb20 fuel pump

Have you replaced the fuel pump?

It could be running but no providing enough pressure for the injectors

[gepsk8]

Check basics first compression test when cold and when hot.

[Crucible]

When its upto temp pull pump fuse/relay and let it stall.

Replace it and start straight away, does it fire now?

CTS maybe out of range also, ie cold voltage to ecu when hot = more fuel. Test or replace.

[Stott69]

Cool, few things to check when I get home. Will need to borrow a compression tester tho

[Crucible]

its often little help people firing off it could be this and that; best to work your way through the manual troubleshooting section so you can rule out components one by one

Logic and evidence. You are very correct my friend.

[Stott69]

Bringing this back up as Im now home and can test stuff. Have pulled codes and Im getting 25: Air-Fuel Ratio Lean Malfunction. Posibly looking at the ignitor? how could I test it?

[Crucible]

vacuum leak, low maf output, low fuel pessure.

[Stott69]

Easyest/cheapest way to check fuel pressure?

[iOnic]

Jam a gauge on

[allencr]

I'd skip the fuel pressure if it's idling OK, redlines 2nd or 3rd, and/or stalls when the FPR return is pinched.
Not just 'pushed' the pedal, but holding it down 1/2 to WOT when starting.


//
//Does it or does it not spark when it isn't starting?????????????
The plugs will be wet & exhaust smell of fuel if the ignition isn't working, and will be dry if there's a fuel problem. Not a pump problem because you already know it works well, but something that may fail when hot like its relay.[/b]