P1651 Code

Mark W · July 5, 2008

My Engine Mgmt light has started to come on after I floor the GS (Full Throttle)

Checked with a reader and its P1651

After about 3 or 4 more starts and driving without full throttle - the light goes back out again - which I think means it hasnt detected the fault again for a few starts/drives.

However, when ever I floor it again - light returns and same code.

So appears the only time there is a problem is when I give it full throttle.

1651 appears to be a Lexus Manufacturer code rather than a standard - and I cant find details of the Lexus meaning anywhere.

Anyone know what it means on a Lex?

Thanks

TigerFish · July 5, 2008

All I could find was P1651 VSV For ACIS Circuit Malfunction. Any P1*** numbers are manufacturer specific so although it is a lexus code, not sure if it covers all models.

There is a description of sorts of that code on this link, but again, not sure how model specific it is clicky

ColinBarber · July 5, 2008

Toyota/Lexus are consistent, that code would be the same across all engines. It makes sense you only get the CEL under full throttle as the ACIS isn't activated until around 4,000 rpm and at a certain minimum throttle angle.

see attached to diagnose the problem

COMP.PDF

INSP.PDF

VSV_INSP.pdf

Mark W · July 6, 2008

Thanks Gents....Linky from Tigerfish and attached files really useful Colin.....appreciated.

Rgds

Mark

newport · July 7, 2008

Mark im thinking of getting a Reader, which one are you using ? ive seen some on eBay at very low prices.

Thanks.

Mark W · July 14, 2008

Bought mine off eBay - unmarked but it uses the ELM327 chipset - which I think they all do to be honest - although I'm no pro ;o)

Came with a load of software on a CD too - all of it was freely available off the internet but saved me the time searching so was quite handy.

Cant remember the store I bought it from - but think it was located in Belfast.....

But as long as have the ELM327 chipset in then should work fine - although I do have a niggling thought in the back of my mind that people have had issues using readers on Mk2 GS300's - or was that the MkI's....you might want to do a search on here because that is where I would have seen it if I had read it.

Hopefully you've not got any probs and thats why you want one? or you just getting one incase?

Mark

TigerFish · July 14, 2008

although I do have a niggling thought in the back of my mind that people have had issues using readers on Mk2 GS300's - or was that the MkI's....you might want to do a search on here because that is where I would have seen it if I had read it.

I think Maneesh had problems on the Mk2 GS300, the Mk1 GS is not OBDII so can't be done full stop.

newport · July 14, 2008

No problems now I changed all 4 O2 sensors, just like to have a reader for future use, ill get one.

The best thing I have done for a long time is changing the tranni fluid (all of it, using Type T-IV) the gear changing is now amazing and im getting better MPG and performance well worth the £94 :shutit: thats just the fluid cost, did the job myself the oil cooler way very easy.

Mark W · August 20, 2008

damn....17 quid for the new vsv valve....3 hours labour to replace....don't you just hate it when they put these cheap parts in such awkward places :-(

b4mky · May 20, 2010

All I could find was P1651 VSV For ACIS Circuit Malfunction. Any P1*** numbers are manufacturer specific so although it is a lexus code, not sure if it covers all models.

There is a description of sorts of that code on this link, but again, not sure how model specific it is clicky

b4mky · May 20, 2010

Re the p1651 / automatic variable swithch valve, do you have any idea where I can find details of a 2002 LS 430 model, thanking you in advance, Ray

b4mky · May 20, 2010

damn....17 quid for the new vsv valve....3 hours labour to replace....don't you just hate it when they put these cheap parts in such awkward places :-(

I guess that is the same as my LS 430, ...£17 for a new acv that sounds cheap. Did you actually fit it yourself ? regards Ray. Your reply would me most helpful as I'm going on a long drive abroad, thanks again.

G_man · August 21, 2011

damn....17 quid for the new vsv valve....3 hours labour to replace....don't you just hate it when they put these cheap parts in such awkward places :-(

I guess that is the same as my LS 430, ...£17 for a new acv that sounds cheap. Did you actually fit it yourself ? regards Ray. Your reply would me most helpful as I'm going on a long drive abroad, thanks again.

I've got the same problem on mine crop up, how did you resolve yours in the end?

Twix · December 20, 2011

Toyota/Lexus are consistent, that code would be the same across all engines. It makes sense you only get the CEL under full throttle as the ACIS isn't activated until around 4,000 rpm and at a certain minimum throttle angle.

see attached to diagnose the problem

Three and a half years later - thank you for these PDF's

This will make life easier

I've also got a code, but now I know where to start!!!

brownridge · October 23, 2012

I have the dreaded P1651 code.....so do the inlet manifolds have to come off? Any tips much appreciated!

thanks allan

TigerFish · October 23, 2012

I have the dreaded P1651 code.....so do the inlet manifolds have to come off? Any tips much appreciated!

thanks allan

Have a read of the pdf's ColinBarber psoted in the second post. Everything should be in there.

G_man · November 6, 2012

the pdf link doesnt work

I ended up covering my EML light up behind the dash, the VSV Valve doesn't affect the running of the car at all, so thought what the hell cover the little git up as it was drivin me nuts with it lit up.

TigerFish · November 6, 2012

the pdf link doesnt work

I ended up covering my EML light up behind the dash, the VSV Valve doesn't affect the running of the car at all, so thought what the hell cover the little git up as it was drivin me nuts with it lit up.

Strange. I've just opened all three of Colins attachments.

The only problem with covering the lamp and not solving the problem is that you won't know when a different fault shows up (unless you read the codes frequently of course). Plus, as I understand it, it is an MOT fail if the lamp doesn't come on with the ignition and then go off once the self test has finished.

brownridge · December 8, 2012

Just an update on my p1651 fault code. After researching the great info here and reaching out to the Lexus Owners club recommended specialists Toyoda Tech near Southampton, they have fixed the issue.

As others have said, it was the ACIS VSV valve. The price of which has gone up to £62.42 plus of course they replaced the gaskets having had to take the inlet manifold off to get to the blessed valve.

The killer, as others have said is that the work involved in getting TO the valve, meant a 7 hour labour charge (OUCH!).

Hopefully all is well now and the dreaded EML light has gone out.

Stuart at Toyoda Tech gave me great confidence that they knew what they were doing ( unlike my Lexus centre at Reading). He did the job exactly when he said he would and communicated well with me. It was worth doing the 1 hour each way journey to drop off and then collect the car to know that you are dealing with folk who know what they are talking about. Thank you Stuart!

TigerFish · December 8, 2012

Glad it is all sorted.

RichS11 · March 3, 2015

Hi gents,

I have this dreaded code. I am trying to find part numbers as I have found the item in the US cheaper than here, but I would like to find out if they're compatible.

Many thanks.