free hit
Low powered V8 0.35 - 0.4 maximum boost - frequency valve issue ? - Page 2 - Induction/Turbo/Manifold/Exhaust - The Lotus Forums #ForTheOwners Jump to content

Low powered V8 0.35 - 0.4 maximum boost - frequency valve issue ?

Recommended Posts

Guest modifiedv8engines

Gunter - thanks for your post.


In my speedy reassembly of my plenum chamber, I made the daft (school boy) mistake of orientating the jubilee clips which attach the flexible pipes to the TB in such a  way that full throttle was only 1/3 with foot nailed to the loud pedal. This is easy to get wrong and something it is worth noting .........even a few of the long term Esprit knowledge based oracles have made a similar mistake but I a not naming them !!


After replacing the boost frequency valve and the two one way valves ( one of the bulk head and the other which goes to the TB) under the recommendation of Dave Hopwood, the car now goes as it was supposed to.


As I menioned in some of my previous posts, I couldnt understand why this car felt so lethargic and basically ....slow. Driving around daily in a nearly 20 year old Land Rover TDi sitting high enough to see over hedges, and then driving the Lotus with arse 6 inches off the ground always seems much faster anyway.


With the 200 Cel cats, centre exit rear pipes and the prevoius problems fixed ( for the time being) the car goes very very well.

Link to post
Share on other sites

Upgrade today to remove Google ads and support TLF.
  • Replies 32
  • Created
  • Last Reply

Top Posters In This Topic

I once received my car back from a service with a reputable specialist with that very same mistake with the jubilee clips!

May: DON'T hit it with a hammer!

Clarkson: Why?

May: Cause it's the tool of a pikey.

Link to post
Share on other sites
Guest modifiedv8engines

Thanks Neal


Cringe time now over and refreshing that others too are honest about the silly mistakes that are made......and by Lotus techs too 


I hated, and I mean hated, this car for having the problems and issues that I have had. Some of these faults where related to poor maintenance whilst others are down to no doubt a limited budget during the vehicles conception/development. Others are just due to poor engineering = cost cutting. 


But when these Esprits are running right, I cant think of another car which offers the same level of perfomance, poise,handling and looks for the money.  


Decent reliable gearbox , intercooler system ( Like Waynes) some better brakes and what a car this would be !! 

Link to post
Share on other sites
  • 10 months later...

Sounds like I have a similar problem to you Paul. I've had the car 4 years now and always been happy with the performance, until I put it on a rolling road yesterday and only making 280 engine hp! I always thought it was the boost gauge which may be inaccurate but now know it was reading correct! Boost is topping out at 5psi in third gear as it hits the redline.

Checked all around for air leaks etc and couldn't find any. Disconnected the feed to the waste gate actuators and took it for a 'gentle' run. Loads of get up and go and boosting between 7-11 psi at half throttle. Bit scary how much power there is!

Tomorrow I'll be ordering a new solenoid valve which will hopefully sort it out. I'll keep the old solenoid valve incase it scares me too much and I can just pop it back in! :)

Link to post
Share on other sites
  • 2 weeks later...

Well new solenoid valve didn't sort the issue. No difference in boost ie between 0.25 and 0.5 bar.

Waiting for my OBD2 scanner to turn up so that I can investigate further. Only reading about 65 to 70 degC coolant temperature so maybe this could be the issue as this is one of the parameters that the ECU looks at?


Link to post
Share on other sites

88 Esprit NA, 89 Esprit Turbo SE, Evora, Evora S, Evora IPS, Evora S IPS, Evora S IPS SR, Evora 400, Elise S1, Elise S1 111s, Evora GT410 Sport

Evora NA

For forum issues, please contact the Moderators. I will aim to respond to emails/PM's Mon-Fri 9-6 GMT. 

Link to post
Share on other sites
Guest modifiedv8engines

Be interested to know how you get on Steve


My car was running pretty well after changing front and rear discs, pads and new suspension. Then the near side front headlamp motor decided to play up so ordered a rebuild kit so this should be rectified next week.


Car out for a run into Norwich this afternoon and simiar problem to yours Steve


Seeing just over 0.5 Bar Boost but only to about 5000 rpm and then it feels as though the wastegates are opening but they are not.


Solenoid (boost frequency valves - Thanks Dave) changed recently, rebuilt turbos, new forge wastegates all set up correctly with vaccum gauge etc etc


Thinking possibly secondary fuel pump


I have Peters software but laptop battery knackered so unless I can find a very very long extension lead, no way to get some data downloaded


Here we go again ..........suppose looking postively the amount of time spent off the road means the milage is low !! > 500 mls in 4 years


If I find the problem will let you know Steve





Edited by modifiedv8engines
Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...