Lexus RX400H on LPG

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Lexus RX400H on LPG

#1 Post by LexusTSB » Tue May 17, 2016 1:33 pm

Hi everyone

I am new to the forum, so please excuse me if this topic has already been discussed.

We have an 06 Lexus RX400h, which we bought last year at 80k miles, and due to my wife's work we hve already done 22k miles on i in the last 11 months.

I am wondering if anyone's running LPG on their hybrids, or am I better off getting an RX300 and getting it converted?

Thanks in advance for your suggestions


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Re: Lexus RX400H on LPG

#2 Post by LPGC » Tue May 17, 2016 2:23 pm

I believe Dai (Classicswede on this forum) has converted some Lexus hybrids.

If the engine features only port petrol injection then LPG conversion will be fairly straightforward as parts to convert port injection engines are rather generic. Some of the engines used in Lexus hybrids feature both port injection and direct injection. Conversion parts for direct injection engines are more vehicle specific (even engine code specific) and LPG systems are not yet available to suit all direct injected engines.

To fully convert an engine which features both port injection and direct injection both types of LPG system (above) would need to be fitted. However, on Lexus/Toyota engines that do feature both port and direct injection, much of the fuelling is done by the port injection system, so as a compromise fitting only a port LPG injection system will realise savings.

Can you find your engine code (this isn't the engine number), it may be in your vehicle documentation or on a sticker somewhere on the vehicle. I would also find the engine code of a late model RX300 before buying (all earlier model vehicles were port injected).

I have converted several direct injected vehicles to LPG with good results and wouldn't put an existing owner of a direct injected vehicle off LPG conversion but I would advise anyone against buying a direct injected vehicle.

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Re: Lexus RX400H on LPG

#3 Post by DodgeRover » Wed May 18, 2016 2:06 pm

My OH has an '02 RX300 on gas which the previous owner had converted at 110k miles, then did 60k over the next 3 years, its a lovely thing only hampered by an apparent need to start on petrol then switch to LPG due to the type of conversion. Has a 77l donut type tank in the spare wheel well, averages about 18mpg stop start and 24 on a run.
Watch out for rust on the older ones though.

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Re: Lexus RX400H on LPG

#4 Post by classicswede » Wed May 18, 2016 4:13 pm

I have done a lot of hybrids. As Simon says some of the 400's use both port and direct injection. I have done one like that but in all honesty it just does not pay off as port injection only accounts for about a third of fuel used unless only driven in town where It is more like half. If it's just port injection then not a problem and conversion is viable. ... 10800.aspx

LPG installer Anglesey North Wales



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