free hit
counters
Vacuum pump runs continuously - Engine/Ancilliaries - The Lotus Forums - Lotus Community Partner #ForTheOwners Jump to content


IGNORED

Vacuum pump runs continuously


AndersL

Recommended Posts

I am completely new with a S4 95 LHD, got the urge to buy it after I was finished with my Chimaera 500. But my vacuum pump runs continuously, it probably means that a hose or fitting is leaking but the question is there  places like these hoses tend to break or is it just follow the hoses and find the hole or component that is broken. i need a little hint if there is one.

Link to comment
Share on other sites


Upgrade today to remove Google ads and support TLF.

WELCOME!!

ON US cars there is a vacuum line diagram affixed to the rear hatch. Look UP. :stuart:

 

Likely suspects are the little "elbows" on the end of the hard plastic vacuum lines. Configurations vary between years, but look under the carpeted sail panel by the right rear quarter glass, and under the dashboard where the heater control vacuum diaphragms are. (For the latter, it is best to remove the radio head unit.)

 

 

  • Like 1

Atwell Haines

'88 Esprit

Succasunna, NJ USA

Link to comment
Share on other sites

Has your exhaust backpressure valve (EBPV) been deactivated? (common modification). If not, sometimes the vacuum hose to the EBPV falls off (The EBPV is located between the catalytic converter and the muffler).

 

Travis' photo of the vacuum circuit:

https://www.thelotusforums.com/forums/topic/81838-gt3-vacuum-pipe/?do=findComment&comment=642657

 

Some of the elbows under the instrument binnacle are visible without pulling the radio to bits.The pipes here are very fine, I'm not sure how much they affect the vacuum system.

By the way, is the car running well? If so, it may be just the vacuum pipes for the heating and ventilation. When the ventilation is selected to fresh air, does the flap under the bonnet (forward luggage compartment lid) open? (just in front of the windscreen). Engine running of course.

Edited by Qavion
memory fail
Link to comment
Share on other sites

I have not been looking for the fault yet, but the car is completely original, so I do not think anything's changed. I found the vacuum drawing sitting over my head, I am a little ashamed. This and an ABS fault is what to expect when I get the time, it goes quite well in idle, but I've only driven it from car transport and in to my warehouse, it was not scheduled that I would buy the car, but it was cheap, I do not have space in the garage yet so it will be here at the company until i cleared out the garage, i have already a Chimaera 500 in the garage,  but I can squeeze in my new Lotus to.

Thanks for all the good advice, now I have info to get started

vacuum line.jpg

Link to comment
Share on other sites

I had the same problem with my S4, found a vacuum hose disconnected behind the dash, down underneath the passenger side. I re-connected the hose to the vent selector valve and the pump stopped running. Later, the pump failed, but found a replacement pretty easily online. Not expensive.

  • Like 1
Link to comment
Share on other sites

  • 1 month later...

Finally I concluded that my vacuum is lost somewhere in the ventilation system, but how the hell do I access the small tubes that I can see through the radio hole, and can see through the right side in my case the passenger side.

Link to comment
Share on other sites

Quote

I was not able to access the small tubes located under the dashboard,

Strange... They are quite visible on Right Hand Drive Cars. You didn't see a rubber T piece under the dashboard? You can gently pull on the tubes to see if they have dislodged. I have a stereo amplifier above the passenger's feet. Perhaps the pipes are above that on your car?

Link to comment
Share on other sites

The least you could have done was paint that bolt black so that it looks OEM. :P  Wait...OEM would be rusty by now, nevermind.

 

More seriously,

Have you checked the plastic T connection on the hard plastic line under the RH sail panel (by the quarter window) yet?  They are famous for separating. And, the blood doesn't rush to your head whilst checking. :happydance:

 

^^  That connection goes forward to provide vacuum to ALL the HVAC valves.

Atwell Haines

'88 Esprit

Succasunna, NJ USA

Link to comment
Share on other sites

No, I have not, I thought that the small pipe went all the way from the pump to under the dashboard and the small valves. which panel is that, there is a small panel down at the floor, or is it up at the A pillar.

Link to comment
Share on other sites

The RH sail panel is the carpeted piece over the gas tank, visible through the rear quarter-glass (behind the door).

 

Worth checking, but as I said early on, configurations varied over the years.

Atwell Haines

'88 Esprit

Succasunna, NJ USA

Link to comment
Share on other sites

Ah, then I misunderstood you before, in that space i am to work with the ventilation hoses that have cracked, there goes indeed the small plastic tube through, but in my case there is no T piece or other connections, the hose disappears into the chassis. in the same space is my MAP sensor and one that I think is a boost sensor and ECU.

 

Link to comment
Share on other sites

  • Gold FFM

Given that most people remove the throttle jack and EBPV, I often wonder whether it would make sense to move the vac pump to the front luggage compartment, or even take a small feed off a brake vacuum servo (if there's one available) and do away with the thing altogether.

Margate Exotics.

Link to comment
Share on other sites

You mention something I have thought about, I have removed EBPV so there is no reason for the pump to sit so far away. I actually think I move it when I've dug my self into and under the dashboard to find the small leak. Thank you for reminding me.

Link to comment
Share on other sites

  • Gold FFM

I know that: I've got one.

A fair few owners (and I could well be one of them in the near future) have junked the Delco, and fitted a standard servo system with a vacuum pump, either electric, or they've fitted an engine-driven pump.

That's why I said 'take a small feed off a brake vacuum servo (if there's one available)'.

Margate Exotics.

Link to comment
Share on other sites

I have read that several people disconnect the ABS valves and replace them with a resistance to fool the ECU, that is what I had in mind to begin with. But I also have to  replace the small pressure tank and pressure switch, so we'll see if any error message disappears. My pump runs constantly.

Link to comment
Share on other sites

  • Gold FFM

Yes, I am planning to cheat the ABS too, I don't like it at all. Here's the link http://www.voicecrystal.com/Esprit/ABS_Disable/

There's a lot of information on TLF about the Delco system, pressure switches, accumulators, so it's definitely worth having a search around here before you do anything.

  • Like 1

Margate Exotics.

Link to comment
Share on other sites

Ian, I just didn't want AndersL to search all over, for something that isn't there! :sofa::lol:

 

One local owner here had to fit a separate vacuum pump in the front boot to provide enough suction for a traditional vacuum operated assist.  He never liked it, it was really noisy/annoying.

 

He finally resolved his issue by buying a V8 Esprit. :devil:

 

 

Atwell Haines

'88 Esprit

Succasunna, NJ USA

Link to comment
Share on other sites

  • Gold FFM

Oh dear! He resolved one issue, but bought a V8 and opened up a good deal more!

The new vac pumps from Hella are very good, and not particularly noisy,either. No more noisy than the Delco hydraulic pump anyway, and as they only run when the brakes are operated shouldn't be obtrusive when combined with an reservoir.

Margate Exotics.

Link to comment
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.

Guest
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...