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superdavelotus

Car won't idle when warm

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Dave,

I had the similar issue in the past, car wouldn't idle & was stalling left & right...it also had a check engine light P1301 (Engine miss fire). It was a capacitor oxidized inside the ECU. I replaced the entire ECU (big money) & the problem was solved. It may not be the same problem but it's easy to try. Just borrow an ECU from someone that owns the same year Esprit. Hope that helps.

Alan

Edited by E5PR1T

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Hi Alan and all, I've never had a engine check light on.

Today I went out in my car 3 times. the first time I went to my local garage to drop off a parcel. cam back to it 20 mins later. It wouldn't start even after 6 times. So I got fed up and started it with the air con on and a little throttle. Took it down the road then pulled over and switched the aircon off. The car just about idled at 600RPM. So i switched it off, waited for a couple of minutes then tried again. started first time! All day it's been fine ever since. On the second and third run out I waited until the car was cool before restarting the engine again.

I plugged the Gendan into the esprit before the third run, just to check the throttle position sensor was working. Yes it was 0-100% with no problems.

I also looked at the short and long fuel trim cycle.

On the Long I am getting a negative figure and bank 1 and bank 2 are reading quite a bit different. Is this right? The Bank 1 Long was -7.03% and bank 2 Long was -1.56% at idle. when revved slighly, it went to zero. On higher revs it went to a small plus value. Is this right?

Dave Walters

ps. Thanks Joey for your guide on resetting the ECU, it came in handy.

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Ditto to what Oneshot - Dave said. Same boat no kids and Simon helped me pay for it. Anyway I hear you can put kids in the closet when you head out for the night :sofa:

This technique works well, Kylie, as long as you remember to toss in a few video games before shutting the door. Bonus points are awarded if unhealthy snack food is tossed in as well. <_<

So in the last 5 years my family went from 2 (me and wife) to 4 (me , wife, 2 children).

But I cannot share the "esprit experience" with the family


Being second is to be the first of the ones who lose.

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Dave :P !


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to name the things if I see them, that's what I call integrity..

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3. When I start, I don't wait 3 seconds. Sometimes I just flick the key all the way round. What a muppet!

Dave, you are no muppet. My guess is that 95% of us go straight to "start" most every time ("POLL?", do I hear "POLL?"). It's the natural thing to do. I only threw it out there as a suggestion for "symptomatic" cars. The Owner's Manual does, in fact, make mention of this technique, but, truth be known, I'm fairly certain that the fuel line(s) retain some degree of pressure even after shutdown. I believe that one of the "tests" for a leaking injector is to dismantle one of the connections on the line (forget exactly where) to see if fuel sprays out (i.e., a spray would indicate that the line is still holding pressure, hence no injector leak). The 3 second wait may be mostly "window dressing," but it can't hurt.


Being second is to be the first of the ones who lose.

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there is an Schrader type valve in the feed line (the RH rail) -an pressure reference can be noticed from that point...


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to name the things if I see them, that's what I call integrity..

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Hi all,

Iam getting lots of fuel pressure because when I had changed my fuel filter, I had to release pressure from the banjo bolt on the cross over pipe towards rear of engine. Fuel sprayed at everywhere even after car had been shut down for several hours.

I have change MAP sensor today but no real improvement. Old one was working fine.

Unplugged throttle position sensor to see what would happen, car wouldn't start. Plugged straight back it and car fired up straight away. I've done some logs using Gendan and confirm that my throttle sensor works fine all the way from 0-100%

Also checked temp sensor and that's fine too.

What's about crank sensor?

Also found an extract in manual on EMM page 18 about the idle air control will be forced closed by the ECU when there's an air intake leak?

Dave

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just as an dump thought: the idle air is supplied by an bypass from the RH-Turbo airduct, right !? What is if the filter on that side is not totally clean. Would that be the problem ..??

possibly no -as the engine does run with higher revs without any problems...hmm ?? I'm confused!


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to name the things if I see them, that's what I call integrity..

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2. I've done the quick easy reset not a factory reflash but I think this is all I need for now. I do have a spare ECU but it off a 97 car. Not sure if it's the same as my 99 GT?

Dave,

There are some differences in the 96&97 ECU/firmware. When I fitted a 98 ECU to my 97 car, I had to have a resistor installed on one of the input lines to simulate a 'charcoal' sensor that isn't on my car, but is on the 98 and later cars. So there are some differences.

Hope you get to the bottom of the problem, I also think that the Esprit community will be a poorer place without your help.

Regards,

Peter.

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Hi Peter,

There are plenty of esprit owners who help out on this forum and in the esprit community more than me. I do enjoy helping Esprit owners out though.

I went out in my Esprit tonight with no problems at all, no stalling etc. Did a few scans this afternoon, my manifold pressure at idle is 38KPa and at WOT is went upto 154KPa. When I turned off the engine, the MAP sensor still reads 98KPa.

A funny thing happened to me tonight when restarting my car. I had my stereo on and CD playing. Restarted the car and it started and idled perfectly. Only trouble is my CD started playing twice as fast!

I've never started the car with the CD playing before so can't say whether this is a new problem?

I've just bought an Alpine CD player at the Lotus Sale, fitted it but thought my Sony Cd player sounded better, so I refitted my Sony head unit this afternoon. It's only a plug in fitment, so nothing to go wrong but why do i get the smurfs if I crank the engine with the CD on?

Dave Walters

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Sounds like you managed to procure one of those rare and special Sony units that has the direct "feedback loop" connectors to the Air Idle Control valve and Throttle Position Sensor, Dave. This extra cost option was specifically designed for cars like the Esprit to assist tempermental startup behavior and dampen out erratic idle. It operates through a special capacitor in the "equalizer" module of the CD player. I have recently sent in my $995.00 cashier's check to "Steve" in Nigeria, and am eagerly awaiting my unit.

Cheers,

John


Being second is to be the first of the ones who lose.

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I went out in my Esprit tonight with no problems at all, no stalling etc. Did a few scans this afternoon, my manifold pressure at idle is 38KPa and at WOT is went up to 154KPa. When I turned off the engine, the MAP sensor still reads 98KPa.

Dave,

The pressure readings look OK to me.

98KPa is close to normal atmospheric pressure of 100KPa (I've seen my MAP when engine is off ranging between 99KPa and 101KPa) This value just reflects the current air pressure, and you must have been in a low pressure environment (was it raining ;-)).

38KPa when engine is idling is also OK. When idling the turbos don't generate enough positive boost to overcome the inherent vacuum that the engine generates whilst sucking in air. When I 1st checked my car I was also concerned about the amount of time the car was running below 100KPa. However, several people confirmed that they all do that.

154KPa is also OK. I'm assuming that you were not doing 130mph+ where you could have expected a higher reading of 175KPa (assuming your car is standard). If I remember correctly you fitted a boost controller, so it should be controlling max boost, and hence the max will depend on how you have set up your controller.

Regards,

Peter.

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Hi Peter,

Many thanks for coming to my rescue and clearing up some info for me. I plugged it into the Gendan again this morning and before I started it, the MAP was reading 100KPa, so that's normal as is my sensor.

I did read somewhere that some idling can mean to air take leak somewhere? Problem is that mine isn't exactly poor idling. When it wants to idle, it does it smoothly and according to manual.

John,

Esprits and mid engine cars were designed to have CD players in, the sound system is in the back. After I posted the last reply, I was waiting for someone to say something similar.

The button on the stereo you mustn't touch is the eject button! :P

Edited by superdavelotus

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David, as Peter noticed: your engine is obviously limited to 0.5bar of boost -save at all !

Edited by G

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to name the things if I see them, that's what I call integrity..

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Hi Gunter,

You've lost me. Iam getting 0.75 all the time.

Dave

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100kPa is 1 bar (1 Atmosphere , o what you want...) -right !? so your 154 is .54bar overboost -or was that not with full power

:confused:

(i hate mathematics -thats for sure..)

Edited by G

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to name the things if I see them, that's what I call integrity..

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The standard V8 ECU doesn't always allow 0.75 bar (175KPa). There are several conditions that I'm aware of that will cause the ECU to limit the boost to a value lower than the max boost. They are:

- Engine not up to temperature.

- Check engine light on.

- High manifold temperature (MAT).

- Speed under 130 mph.

- What gear is selected. max only available in 5th gear.

As always, Lotus were fighting the 'low' torque limits of the Renault gearbox and I wouldn't be surprised if they weren't also fighting rear grip, as even with the standard boost behavior it's far to easy to spin the wheels, especially when damp.

Obviously, if Dave still has his after market boost controller connected, then his car could be displaying different boost behaviour.

Regards,

Peter.

Edited by peter_england99

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Hi All,

Max boost with the factory standard V8 software is 0,75 bar, but NOT all the time ...

Most of the time its much less than 0,75 bar. It depends on the rpm, TPS, selected gear and many more parametres ...

Here is a graph that will show you how a stock V8's boost should look like:

V8%20Boost%20Standard.jpg

Cheers

Marcus


Marcus

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Hi all,

Can anyone tell me how long I need to leave my ECU unplugged from it's harness for a reset? I know reading Joey's guide it says overnight but is there a particular time? I think I've got to the bottom of my problem but just need to try one more thing.

Dave Walters

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I know it's different but my 4cyl ECU resets after about 5 seconds! :)


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

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the time ,necessary for an battery change (unplug/plug of the cables and lift it out/in ) was always enough on my. It had to learn idle every time i had done this.. . [3 batteries in total :) ]

Edited by G

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to name the things if I see them, that's what I call integrity..

*********************************************************************

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Dave,

I've just looked in the service notes and can't find any reference to resetting the ECU by removing the power supply. However, you can force a reset via the "Tech 1" scanner/OBDII reader. Have you got access to a "Tech 1"?

In regards, to the time taken to reset the ECU. I would guess that a few minutes (maybe 20) should be enough. To prove that the ECU has been reset you could check the long term trim before and after the reset and check that it goes to 0.

Sorry to not be able to give you a proper answer.

Regards,

Peter.

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Hi Peter,

Don't have a tech1 only Laptop based software and cable which doesn't allow you to reset the ECU. I'll leave it unplugged overnight just to be sure and try in morning.

I will check the long trim when I plug it back in as Iam running with another ECU at the moment which is on top of the old one.

If it's not reset then I'll book it into Chistopher Neils who are my nearest dealer.

Dave Walters

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