Hopefully may have a fix and method of testing
now done three of these all with the same fault.

Not throttle body, harness, ecu or position switch

As with the previous posts the fault is in the ecu wiring. The faults I have found are with the computer earth in the top plug of the ecu
Remove battery box and ecu
Testing check continuity from the throttle body two light orange wires and four grey to the centre plug on the ecu to do this you will need to remove the plug wire tie bands on the plug backs, if no continuity repair other wise follow on

remove plug backs pull computer to front of car so you can reconect battery.
start car and run up to engine is warm by doing this you open the throttle body remove battery earth to clear memory in ecu and reconect battery

put key in to ignition and you should now be able to here the throttle body. the sound should be a low buzzing noise as the ecu holds the body open due to engine being warm.
as you now have access to the ecu plugs if you move them from side to side you will here the throttle body motor moving in and out and you have now found the fault
the faults I have found relate to the top plug on the ecu the two black earth wires for the computer.

to clean there is no easy way to clean the conection what I do is remove the rubber seal around the plug to allow more movement in the plug using either electomex or WD40 liberally spray conectors and keep working form side to side unpluging and repluging, on occasions I
have had to clean and waggle the plugs for about 15 min until you dont get the trottle motor moving in and out and hey presto you have cured your bad connections to the computer and dont get the throttle body error so to recap the injection light and throtle body error appears to flag up due to poor computer earth conections

hope this will help a lot of disguntled Laguna owners

Aphelion RTE

 

I've just experienced the same problem. The garage replaced the throttle body and said it was fixed but it wasn't.

The problem is that there is a problem with the ECU recognising and registering the new part (or whatever the technical term for this is) the garage perservered and after 3 goes of reprogramming the ECU it finally worked and now the problem has totally gone (touch wood).

 

I have Renault laguna 1.8 16v 2002. It has an on going problem whereby after travelling about 8 to 10 miles if I stop and start the journey again, the car starts ok but after few minutes the electrical fault light comes on and the engine starts to rev betwwen 2000 and 4000 revs. and the accelator has no control over the engine speed. The car has been in the garage and they have replaced throttle body, spark plugs and the injector E.C.U. After the ecu was replaced car was ok for couple of months and now the problem have again surfaced and is getting worse. Initially problem was occuring one a month or so but now it is occuring regularly whenever and I make start stop journeys. The distance of the journey I thionk is not important but whenever the car is stopped and restarted within half an or so the problem occurs . If the car is left standing for few hours and then started it will take longer for the problem to reoccur.
I shall be greately obliged if anyone can suggest a solution.
Many thanks in advance.

Kuildip Obhi

this is the
fuel sensor not regalater claytyn

 

I also have the same fault, had the cat con changed, but diagnostic still pointed to the throttle body. But now it making me stall when i stop due it irratic revs, and the engine revs at 2000, and takes about 30 mins to reset. My question is....i've found a 2nd hand throttle body, with the same part numbers, so can i just fit it and drive, or does it need to be programmed into the ECU by a garage/renault service engineer.

Regards
Paul

 

I have a similar problem where the engine revs on its own and I can be driving and take my foot off the accelerator and the car will still be doing the same speed as it was when I had my foot on the accelerator . The local garage have said its a switch gone . Just wondering if anyone else has come across this problem before and if so how easy is it to change the switch as I really dont fancy paying the £200 plus Ive been quoted so far by the garage .

 

Hi everyone, 1st post so please go easy!

Was there ever any photos of the ECU wiring being accessed and cleaned? Renault have quoted £1700 for ECU, Throttle Body and wiring loom and although I'm a very bad mechanic, I'd quite like to give this trick a go before the car gets scrapped!

All help appreciated.

 

I have just experienced the same problem with my 1.6 Tourer. Fortunately I was able to get the services of an ex Renault mechanic who had a diagnostic computer and it read that there was an electrical fault in the throttle body. He then disconnected the plug at the throttle body end of the wiring, gave it a good clean sprayed it with WD40 and then checked the connections were in the right position, reconnected and did a test drive and the problem appears to have gone.
I have not had the problem return so far so I am keeping my fingers crossed. If it has been fixed it has only cost me €30.

 

I have a Renault Laguna 2 2002 F5R 2.0 IDE
It was working fine until one day whilst I was driving the dashboard lit up like a christmas tree and then the engine shut off. I waited for about ten minutes and then restarted. I managed to get home, approx 9 miles and had to restart about two or three times.

AA diagnostics = fuel problem. Changed my plugs (Bosch @ Halfords)

I have changed the fuel pump/filter unit that sits in the fuel tank, the complete fuel rail + injectors + fuel pressure regulator.
Same problem but now the car can start from cold, I can leave it idleing for about 15 minutes reving occassionally....no problem...then there is a moment when the engine is hot and the SERV + management + a few others and it shuts off. At that point I can restart but the vehicle goes for about 50 yards and shuts off.
I have searched the forum but I have not been able to find a similar topic, pulling my hair out, can someone please help!

 

After doing some extensive research onthis forum I have removed and cleaned up the ECU and contacts, removed throttle body and cleaned, removed TDC sensor and cleaned. Replaced spark plugs with Renault plugs. When purchasing the plugs inormed Renault of the cars problems and was informed that it was an ongoing problem and that I should talk to Renault customer care and state that I knew there is an ongoing issue with this. The service department checked that I did not need a ECU update and told me that the car probably needed a 'clean up'. I will put it all back tomorrow and fire it up.

 

I don't belive the problem suffered by the IDE engines are the same as that of the 1.8 F4P the orginal subject of this thread. IIRC the IDE engines are notorious for being trouble some the fuel regulator being a common problem.

 

Put it all back, fired up car, started first time. Left idleing for 10 mins, noticed orange engine light on dash board, went for a spin....great, after about 20 mins stopped to talk to someone...started up again....BANG! It all lights up again...limp mode home!

 

:dSuccess at last!
After heartfelt prayer...solution!
Took out ECU....again, checked all connections etc.
Car running better but still same problem.
Was just about to check out six cables from throttle body to ECU for continuity when a friend suggested start engine and disconnect throtle body cable.
Did that and engine became lumpy and eventually shut down.
Diagnosis...cable is OK.
Took out throttle body...again!
Took out four star screws and gently prised the lid off trying not to break anything...these are 250 all up fitted from Renault.
A flat piece of the inner black lid breaks away which needs to be put back into place on re assembly.
Inside the cap had a greasy film with lots of carbon deposit, sprayed out and thoroughly cleaned.
Next there are four contacts that look like metalic eyelashes that make contact with with the inside of the cover, carefully cover over the rest of the throttle body and spray clean without getting any contact cleaner on the electrics, then slightly bend them upwards so that when you replace the cover it makes good contact. The black piece needs to be put back exactly in position, clean off rubber seal, replace lid carefully and hold firmly in position whilst screwing in four star screws.
Replace throttle body.
So, after replacing the pump in fuel tank, complete fuel rail including the fuel regulator...all bought from Renault Specialist for 300, a new set of spark plugs, cleaning of ALL sensors, spray cleaning all engine wireing connections, dismantleing the throttle body, and feverent prayer my Laguna now runs like a rocket, it is the best that I have had this car going...and the bonus...I know how to service my car...properly.

 

Hi there i have the same problem with my lagunaII 1.6 and am interested in trying to fix the problem, where is the ECU located and how difficult is it to remove etc?

 

Hi mate i had the same problem with my laguna , where it was reving forever what a nightmare .
Your best is to replace your throttle body , pedel and get a hole is ecu kit .
When replacing the ecu make sure it its been resetted and the software updated

 

Well the limp-gimp home mode just does not want to go away,I have been following this topic for well over a year now, yes my Lag is doing exactly what Kuldip discribes, And yes I have had all the checks possible done and still theres a problem. To me it seems Renault are just turning a blind eye to the problem, typical of the Froggs. All I do now is just live with the fact that French cars are a bag of ****. I will never buy French products again.

 

Hello,

Just read whole tread and wonder why nobody checks the relay that are next to battery. I had the same problem. After cleaning the contacts of this relay (first on right) the problem was solved. After year (2 days ago) problem came back. When pull off this relay and put it back everything is OK, but till next restart. This relay is simple enough, inside there is contacts to, but need to disassemble it and clean it with sand paper. When contact don't release itself, wrong information is sent to fuel system. Tomorrow i will bought new relays (will change whole 3) and gave you update. Don't spend money to change whole cabling or bought new ECU or Throttle body, the problem is in this relay.

P.S. My Laguna 2 is 1.8 16V running on LPG

 

sun_project you will be a diamond if your right about the relays been at fault, please do keep me posted on your results,and prices of the relays:d:d:d

 

Think i have found the solution after spending hours on line. Fuel pressure regulator.
Trying to get hold of one now.
http://www.honestjohn.co.uk/forum/post/index.htm?t=87606
http://www.renault4.co.uk/forum/showthread.php?t=2141&page=2

 

please check these links.
will be changing mine this week.
http://www.honestjohn.co.uk/forum/post/index.htm?t=87606

http://www.renault4.co.uk/forum/showthread.php?t=2141&page=2

:loser::loser:

 

does this apply to the Laguna ll 1.8 16 valve dimonique petrol, or just the IDE,mate? to be honest with you after reading almost all of the posts on the forum it seems to me we are all suffering the same problem of Limp home mode, where there is no response from the throttle peddle,engine revs between 2000 and 3000 will only drive at 40 mph to get you some place safe, stop the the car and after a short time it will be fine only to start again down the road.. do we realy know what the problem is or are we all clutching at straws???

 

Mine is a 2litre dynamique ide. The part cost me £220 and is hard to get hold of, but looking at the links i put up it all seems to make sense now.
Having it fitted Thursday so will keep you posted.

 

Sorry i was wrong. When i pull off the relay i restart the throttle body. This solve the problem for once. This can be done even if you pull off the cables that goes into throttle, this is easiest way (it's very difficult to pull off this relay). So the guy who say the problem is in contacts is right. I used spray against rust to spray the contacts in throttle body connection and no problem for a week. Last year i checked contacts in the ECU but it's not possible this contacts to be oxidized. But it's much realistic the contact in the throttle to have oxide.
Hope this low tech solution to have success

 

I realy cant see it been electrical problem,It has got to be deep inside the throttle where the problem is been caused.

 

Regulator replaced and she is running well. So far so good.:d

 

hi guys

after 2months of putting up with the wifes car as she would notdrive because of the dreaded fuel injection fault. i think i have finally got to the bottom of it. we first replaced the throttle body for a new one when the problem persisted decided to back that as it was not the cause of the problem. although must say picked up a new one for £184 inc of vat and delivery so good price.

we took off the throttle pedal pretentionmeter is adjustable on my model which is a 1.8 16v privelege. it was not lined up so adjusted it. 60miles now no problems was going 3 or 4 times in a 15 mile journey will replace it altogether if i make it to 250miles as the track inside it is worn.

hope this helps this horrible problem for some of you.


hope to have happy driving time now

 

Thanks i will try that hope it works :d

 

Hi all. I recently saw this thread and maybe I have solution for this. No response to pedal position is caused because car is safe mode. This hapened to me on clio 1.6 16v and some other models with f4r engines. When car start to revs between 2000-4000 revs, just shut it of, disconnect battery gnd terminal and unplug throtle body, wait couple of minutes, reconnect it and start the engine. That is how i resolved my problems. It might be that you need just to clean battery terminals.