swanz

Hi… looking for some ideas on this issue…. Getting intermittent start. Cleaned air intake, replaced all coils and sparks, rebuilt fuel pump assembly (new filter, pump and pressure regulator). Ran consistent all week. Will crank and fire but won’t hold. I have a 2002 es300. Love it and first time not to start in 15 years I have had this beauty

Arsenii

Hello,

Where did you get all the replacement parts?
What do you mean by a Rebuilt Fuel Pump..? May be just me but I've never heard of those..

Sounds like a common issue with owners around this forum of people throwing parts on problems, which usually results in even more issues, here is a thread about it.

In short, I would put all the original parts back in, except for the pump maybe, as they tend to fail after sitting dry for a while, you may need to get a Denso replacement here. See if it changes anything, if nothing else, it will at least give you a starting point.

Hope this helps and best of luck!

isfvss

That sounds like fuel related problem have you measured the fuel pressure, any codes ??

swanz

Fuel pressure good on the gauges… no codes unfortunately

swanz

Did all denso or oem parts

fortitude

have a look at this doc

swanz

Many thanks. Will work this tomorrow and update u

fortitude

C/OPN relay part number is the same for horn relay based on below links

https://www.japan-parts.eu/lexus/us/...-system#85910A

https://www.japan-parts.eu/lexus/us/...mputer/2#86530

Open the fuse / relay box in the engine bay

I believe the horn relay is next to C/OPN
Look at both, confirm they are same
Check that horn works, then switch relays. See if it solves it

swanz

So switched the relays and didn’t fix it. Can hear relay engage. Moving on to testing sensors as in the diagnosis sheet. ECM ok.

swanz

continues to have no codes and all other data looks right even when no start on computer