[Beerman]

Hoping someone can help me diagnose a couple vacuum line mysteries on my '88 Esprit. These are both located on the RH side of the car in the area above the rear wheel well. There's a lot of vacuum piping running around in this area.

1. The hose attached to port 2 of what I think is the EBP solenoid valve is not connected to anything on the other end. See pic...the line with the little red zip tie on it. From the diagram in the Service Notes it looks like port 2 just vents to atmospheric so this is probably OK. Sound right?

2. There's a very small diameter semi-rigid plastic pipe hanging down which isn't connected to anything. It looks like it runs forward up the RH roof channel, presumably attaching to something up front perhaps in the luggage area. I know there's some vacuum piping associated with the heater box (my heater isn't supplying heat), is this the vacuum supply line?

Any help is appreciated. Thanks.

 

[Vulcan Grey]

the small hard line goes to the heater controls below the stereo, which is why you aren't getting heat.

I don't know the '88 Esprit at all, but the other vacuum line on the 89+ cars is for the throttle jack, and EBPV.

 

[G8nightman]

Make sure you didnt brun out your vaccum pump I think it will keep pumping if the line is left open like that.

 

[MidLifeZ]

The hard line to the front in mine got disconnected during my stereo install. Had to assume the lotus position in right side with a flash light to locate it..

 

[Vulcan Grey]

Make sure you didnt brun out your vaccum pump I think it will keep pumping if the line is left open like that.

The '88 has a mechanical vacuum pump connected to the water pump belt, it always turns with the engine.

With a large vacuum leak, your brakes should also be very hard, and not working very well. You will need to verify vacuum at the front brake booster once you get everything hooked up.

 

[sleekgt]

Here's my 88 Esprit passenger side hose routing - I took these pictures for Atwell's reference but should be worthwhile to at least compare your 88 (see URL below for 33 photo album):

Full photo spread here:

1988 Lotus Esprit Turbo Right Side Hose Routing Photos by eberin | Photobucket

 

[carbuff]

Sheet 43.03C of the '88 - '92 Esprit Parts List has a very clear picture of the vacuum lines. If the lines in the car are OE, they have colored stripes to help ID them, and the colors are noted in the parts descriptions.

You can buy Paint Pens and re-stripe any vacuum lines that you replace. (This tip thanks to Type82)

The original vacuum line to the EBPV was a hard plastic line with soft "elbows" on each end, as was the heater supply. Watch those elbows (like item 33 and 51)... when they get old the lines fall out easily. Don't ask me how I know this. :facepalm

 

[esprit888]

That small rigid plastic line is to your heater and A/C flaps. It has pulled out of one of the rubber reducers ( you can just see one in your first pic, lower left hand side) as Atwell says some are elbows, your pic shows a straight one. You are in the right area, dig around until you find one that doesn't have a small plastic line going into it, could even be the one you can see in your pic, either pulled out or broken. The factory apply an adhesive to keep them in but over the years it hardens and they can easily be pulled out. I have a spare 88 vac solenoid assembly in the garage and can take a pic if you need one.
Colin

 

[Beerman]

Thank you gentlemen, very helpful information. Let me process some of the data and take another look in that area where the vac lines are routed and see what I can determine...will report back shortly.

Thanks again.

 

[carbuff]

The factory applies an adhesive to keep them in

I learn something new every day! :up:

 

[Beerman]

Just a quick update here.

It looks like the vacuum line which went to nothing is fine as-is. That port of the EBP solenoid valve this pipe is connected to on the one end vents to atmosphere per the Service Notes. So, all OK here.

I did connect the vacuum line supplying vacuum to the cabin heater box...connected it in (with a T connection) to the main vacuum supply line coming from the vacuum pump. This improved things in the cabin, there's heat now. However, the heat is leaking out from behind the dash pod, not coming from the vents...so it looks like some vent piping has probably fallen off or the actuation of the flaps isn't working right. I'll be assuming the Lotus position for a while to check it out this weekend. Another problem to sort out.

The fun continues!

 

[Vulcan Grey]

remove the seat and steering wheel to make it easier to get down there. They are very easy to remove.

Don't forget to check vacuum at the brake booster. I once had the mechanical vacuum pump die on me while driving, I almost wasn't able to stop from 45mph for a red light. IIRC it takes ~8x leg force to stop without the vacuum booster.

 

[carbuff]

... the heat is leaking out from behind the dash pod, not coming from the vents...so it looks like some vent piping has probably fallen off or the actuation of the flaps isn't working right. I'll be assuming the Lotus position for a while to check it out this weekend. Another problem to sort out.

While it's always refreshing and FUN to assume the Lotus Position remember, YOU WILL NEVER GET HEAT OUT OF THE DASH VENTS by design. They are "cold air (and A/C) only" .

The defrost and floor vents are the only sources of heat in the Lotus system. There is one "dryer hose" connected to the defrost outlet in the binnacle, so while you are under there, make sure it's connected. (It isn't clamped or anything, just a press-on).

 

[e-spree]

And make sure the dash vents are turned shut when you want heat.

 

[MidLifeZ]

Something I did, might be useful to others with warmer weather now... I found that the dash vents on passenger side pointing up basically just cooled the windshield.. so got a couple of boost gauge holders in faux carbon fiber. Cut in half, glued some plastic to them as "legs" which slide in between the vents and the housing for them. Really made a difference in airflow to passenger!

 

[carbuff]

Wow Ken,

I LIKE your checkerboard floormats!

 

[Beerman]

While it's always refreshing and FUN to assume the Lotus Position remember, YOU WILL NEVER GET HEAT OUT OF THE DASH VENTS by design. They are "cold air (and A/C) only" .

The defrost and floor vents are the only sources of heat in the Lotus system. There is one "dryer hose" connected to the defrost outlet in the binnacle, so while you are under there, make sure it's connected. (It isn't clamped or anything, just a press-on).

Ah, thank you. Guess I should have read the owners manual a little more closely......

Cheers.

 

[MidLifeZ]

Wow Ken,

I LIKE your checkerboard floormats!

BWAHAHAHA! That is actually a bag from a store...

<off topic> Carpet out of another Esprit shipped off to the same guy who did the floor mats during the group buy.. Having same done to replace all the interior carpet! WOOT!

 

[carbuff]

Ah, thank you. Guess I should have read the owners manual a little more closely......

.

^^^ The most unread volume in the history of published works...

 

[carbuff]

That small rigid plastic line is to your heater and A/C flaps. It has pulled out of one of the rubber reducers ( you can just see one in your first pic, lower left hand side) as Atwell says some are elbows, your pic shows a straight one.... The factory apply an adhesive to keep them in but over the years it hardens and they can easily be pulled out.


Colin

So today my Esprit was idling kinda funky with stiff brakes, so I looked at the vacuum line we were talking about. It had come off! :facepalm

Dab 'o RTV (plus I re-routed it to reduce the stress) and I'm ALL SET.


PS: The "reducer" was shaped like a pair of bird WINGS. Figures.

rotfl :thwack: