Boost Pressure only reaching 0.5-0.75bar

[EspritMiltonKeynes]

1990 SE (No Dump Valve)

A couple of days ago (having already put a thousand miles on my new car to get accustomed to driving it) I decided to bite the bullet and do what what I've really been wanting to do ever since I started. I took it on a proper 'burn out' down the Private test track, road conditions were good, very little traffic, and I concluded that as irresponsible as my actions would I just HAD to do it (partly just to see that everything really was working).

It was about 3 in the morning and I managed to get up to about 135mph, I think 6000revs but the boost pressure was barely over 0.5bar, infact the only way I could raise it higher was to 'stab' at the throttle whereby the needle would briefly kick up to about 0.75. I'm fairly convinced I'd reached the car's max speed - I don't think it would go any higher.

Now obviously SEs are supposed to go to 165mph, and I presume have transient boost pressures anywhere up to 1.2bar. 7000rpm should be wholly attainable so what's wrong with mine?

I'm thinking there might be a fracture in the turbo casing on the compressor side. So when the boost pressure get beyond 0.5bar it just starts escaping from a leak somewhere, there certainly is a funny hiss coming from somewhere. I'm also pretty sure I've got fuel line problems - the whole cab just stinks of optimax

It's just not as espritely as turbo esprit should be...

PS... What I did that night was totally irresponsible and this thread is not meant in any way to glamourise speeding.

[Evil_Dr_Fish]

Spare us the legal disclaimers! We're all Esprit drivers here and have them for just one reason!!

<--------- See!

I assume you have no check engine light? That would limit boost to .45 Bar....

[EspritMiltonKeynes]

Spare us the legal disclaimers! We're all Esprit drivers here and have them for just one reason!!

<--------- See!

I assume you have no check engine light? That would limit boost to .45 Bar....

<{POST_SNAPBACK}>

Hahaha... yeah everything's normal lol. Oil and water temp.s fine. No check engine lights, the car does rattle to hell but that's just the crumby SE suspension - I'll get some sport 350 springs oneday

[Evil_Dr_Fish]

Kato had S350 Susp. on his and took it off

The V8 weighs so much more that your car ends up on tip-toes and is waaay to stiff...

GT3 made more sense iirc but read Kato's updates / News from Hethel page!

[WayneB]

Maybe your charge cooler pump is shot and the ECM is limiting the boost? (you need to speak to Paul C about this, as Im just a dumb S3 Turbo owner)

[Paul C]

Maybe your charge cooler pump is shot and the ECM is limiting the boost? (you need to speak to Paul C about this, as Im just a dumb S3 Turbo owner)

<{POST_SNAPBACK}>

Ahhh, but an S3 owner with some knowledge!

Whereas i'm a Stevens owner with limited Knowledge...

Sounds like a good guess this though, have you done the

chargecooler touch test? (should be proper cold, but test it

immediately after stopping before it heatsoaks). With the

chargecooler not working then in theory you have an 'Esprit

Turbo', but i think Wayne is right here and the ECU would

rob you of boost.

The ECU can limit boost with no checklight in certain conditions

like Check light failure, low coolant, coolant not up to temp, and

i'm sure there are some other ones too...

Every time i comment on such things, i get hailed as an expert

(which i ain't!!!) and the legend grows! So if anyone with real knowledge

can chip in here, Please do!

Dermot?

[pitstoppete]

ESP. M K?

is your boost gauge going round to 0.5 with about 3/4 throttle and 0.75 with full throttle? if it is, looks like the gauge is a bit wrong. if its all std, should be more like spot on 0.65 max, then 0.85 bar WOT. occasionally in fourth and if your gauge is right, u might see 1.0 exactly momentarily. this is if everything is in good condition.

check to see if it really has got full throttle. get a helper to floor it engine off!, and try to open the throttles by hand a bit more. IIRC 95~% aint enough

check the boost gauge sensor wires/connector under the right hand engine side cover

as the guys say, std problem of knackered C/Cooler pump stops it going full fun factor.

maybe start to look at the wastegate/hoses/solenoid area for problems.

If you have a loud hiss, that clearly needs investigation. dodgy red turbo hoses at chargecooler/turbo housing loose?/split or worn through black hose to MAP sensor?

FREESCAN is required for a proper diagnosis

[pitstoppete]

fuel stink is the link breather over the top between the tanks. take the side engine covers off and have a look.

[Paul C]

Oh, and the speed issue could be the speedo.

I have been with another Esprit on a private test road at 160mph.

His car reads 160mph.

My GPS reads 160mph.

My speedo reads 140mph.

Therefore i trust my GPS for accurate speed, which is handy as it

is used for speed camera location detection, so when i look at the

warning i see current correct speed alongside.

PS, I use the 'Private test road' always. I see you mention a particular

stretch of public road in your post, there have been recent convictions

with online video footage and noticeboards used in prosecution. I'll edit

the precise info out for you. put it back if you want, i won't mess again!

[WayneB]

So I presume as long as your car is pulling 7000 rpm in 5th gear you are doing 165 mph? (on private test track honing driving skills)

[EspritMiltonKeynes]

Wow... thanks everyone for your replies, and so quick as well

Interesting ideas, I'll do the chargecooler touch test next time I'm about with and let you know.

The check engine light does work - it comes on momentarily when I start up.

Very interesting points about the faulty speedo - because I was scared to hell at just 100mph driving down the 'private track test road' It felt like I was going much faster than the speedo stated particularly as I seemed to get from leicester to rugby in about 8 mins on this particular stretch of 'private road'

Yeah, I have read the things on Kato's site about suspension mods, glad you reminded me of te problems of putting V8 springs on lightweight S-Cars. If i do get them changed I'll go for GT3.

Pitstoppete - you're now talking way beyond my limit of technical expertise but I think I can understand what your saying and it sounds pretty likely to be the problem. I might leave it to someone else to sort out though, B) sounds like a job for Paul Matty....

[Paul C]

So I presume as long as your car is pulling 7000 rpm in 5th gear you are doing 165 mph? (on private test track honing driving skills)

<{POST_SNAPBACK}>

Eh, What??!!

Sounds like i'd need a slide rule or summink to work that out.

TBH, i think every Esprit guage and sender should have some

+/-10% 'parts bin' rule applied to its reading. Man, if i corner

or brake hard then the dash tells me i'm running out of various

things that i'm actually not.

The most 'accurate' guage on my SE at the moment is the

'passenger door speed sensor', this works by allowing vast

quanitites of compressed and turbulent air into the car at more

or less exactly the 100mph mark. the sensor is constructed by

means of a tired and spongy door seal and a slightly loose door

check plate.

...tune in next week for my 0-60 with an egg timer

[pitstoppete]

EMK. can you do a nearby search (begging post) for some one with Freescan, and ask them to give u a hand. I would gladly, but i'm a fare few miles away

any Lotus (not interested in proper Lotus cars just new ones) dealer and most specialists wont be as switched on as the collective grey matter of all us SE owners, once we've seen the freescan log file.

[Paul C]

EMK. can you do a nearby search (begging post) for some one with Freescan, and ask them to give u a hand. I would gladly, but i'm a fare few miles away

any Lotus (not interested in proper Lotus cars just new ones) dealer and most specialists wont be as switched on as the collective grey matter of all us SE owners, once we've seen the freescan log file.

<{POST_SNAPBACK}>

Best bet - get your ass to the oxford meet,

there will be more advice (and new friends)

there than you will be able to remember!

[pitstoppete]

I'll be bringing both my laptops with freescan with me. in fact one is wired in permanently at the moment after all the troubles i've had. turn the brightness up, bung it on the seat next to u, and watch the virtual dash as u hoon about testing the boost...

PS paul, ive finally fitted your plastic dash gauge thingies. the business with the new dash woodwork

Best bet - get your ass to the oxford meet,

there will be more advice (and new friends)

there than you will be able to remember!

<{POST_SNAPBACK}>

[Evil_Dr_Fish]

Re: Suspension - probably not worth fitting GT3 stuff now and waiting a while and getting the all new, recently approved and designed especially for your car by Lotus, the world renowned handling experts, suspension!

(Again, see Kato's page on his trip to Hethel this week )

[Bibs]

I thought GT3's used the same suspension setup as the S4s so it would work on an SE well. It'll be cheap too when the new stuff comes out and everyone 'upgrades'.

[Evil_Dr_Fish]

There were a few differences between the SE and S4 suspension setup - the SE is known for being 'twitchy' relative to S4 and onward cars, so the new stuff may be better suited to take account of the diffferences.

[EspritMiltonKeynes]

RE PETE: Yeah, I'll defintely come down to the Oxford meet if I can make it and if someone with Freescan would lend me their grey matter as well that would be even better. When is the next meet?

RE: Chargecooler touch test. I wouldn't say it was cold, but it was cool enough to put your hand on. Unlike the rest of the engine... As I'm reading more and more into it I'm beginning to think a lot of the things on the car are coming up for replacement. 15years and 56700 miles (almost 3000 in the last fortnight)... at least it's still working!

[Evil_Dr_Fish]

Sounds like your CC pump may be iffy

From what I've read, it should actually be COLD!

[EspritMiltonKeynes]

Yep - the chargecooler def' isn't as cold as it should be. Also discovered an exhaust hole today. The list mounts....

[CNH]

The CC box should feel like cold metal. Almost feels like a copper or steel water water pipe.

[Paul C]

Yep - the chargecooler def' isn't as cold as it should be. Also discovered an exhaust hole today. The list mounts....

<{POST_SNAPBACK}>

We all got lists

Lists are cool as you know what needs doing and what the cause is.

Rattles, on the other hand...

[EspritMiltonKeynes]

Oh I'll have rattles too before you know it! Then come the nightmares, and before you know it.... COUNSELLING

[Paul C]

Oh I'll have rattles too before you know it! Then come the nightmares, and before you know it.... COUNSELLING

<{POST_SNAPBACK}>

Drink. Works for me!