Independent Renault Forums banner

Power loss when hot

Tags
hot loss power
2K views 7 replies 6 participants last post by  neildfowler 
#1 ·
Hi. I replaced my cam cover gasket some time ago on my 2004 Espace MK iv to correct an oil leak.

I deleted the EGR by removing the metal return gas pipe, and adding blank plates. The EGR remains in place and connected electronically.

Since the these changes, the engine loses power in a kangaroo fashion when it reaches the hot operating temperature. There is also a "whooshing" gasp for air from the engine as the power drops.

Power is resumed above 2000 revs. Sometimes a cloud of smoke will appear when power resumes.

On observation, the "whoosh" comes from the air filter box and connected pipes; power loss seems to be a result of the air being restricted. I think this might be the case because the air intake box gets sucked inwards towards the engine as the whoosh happens.

I have replaced the MAP , water temp and MAF sensors, though no improvement.

It has gotten worse over time. I used to be able to go 50 miles on the motorway if I kept the revs high. Now the car will come to a stop and just idle until it cools down, then power returns.

Any thoughts are much appreciated. Thanks in advance for reading.
 
See less See more
#2 ·
Since the these changes, the engine loses power in a kangaroo fashion when it reaches the hot operating temperature. There is also a "whooshing" gasp for air from the engine as the power drops.
You kinda diagnosed the problem and prognosis right there from my point of view..

EGR valve and ancillary operations are there for a reason right?

Re-enable / remove blanking plate for EGR valve and see what happens, is what I would do.
 
#3 ·
Check your pipes are secure, going to and from your turbo, if one of the clips are slightly lose, it will take a while to build up your boost, hence your woosh.
Egr was initially fitted to vehicles, to try and keep emission levels low, it is re burning waste gases from your engine, but mixed with new fuel/air, so breaking these gases down further.
If blanked off, usually the car runs better,with more power
 
#5 ·
  • Like
Reactions: neildfowler
#4 ·
On observation, the "whoosh" comes from the air filter box and connected pipes; power loss seems to be a result of the air being restricted. I think this might be the case because the air intake box gets sucked inwards towards the engine as the whoosh happens.
This seems to be why the power is disappearing, no air and engine won't run, lose power, overfuel and blow smoke (unburnt fuel)

Tried a new air filter?
Check over inlet pipes for any restriction or blockage.
Check that pipes are not being sucked closed due to weakness/age/structural failure.
Some engines, not sure if yours is one, have a temperature operated air flap that diverts intake from engine bay to outside as engine warms.

Just some thoughts.
 
#7 ·
Id pull the inlet pipe from the turbo and check for play.
when things warm they get bigger when metal had gaps, its got a wobble the gap goes and things stick. you may need to actually service the system and pipe to remove the soot build up. usually this gets stuck around the ERG causing problems, but it will just cause problems else where.
 
#8 ·
Cheers people. I am very grateful for your amazing insights and for taking time to respond. My work has prevented me from looking at the car until now, so apologies for late response. I looked as best as I could, but found no problems with splits or loose pipes. The mechanic is looking at it today as he can get the beast on a lift thingy.

The mechanic showed me how the waste-gate operates and causes the power loss. When this turns on (when operated automatically by the ecu or something), there is power loss. The gate then turns off, and the power returns. The power loss and regain definitely happens as the gate opens and closes. When the vacuum pipe is removed from the waste-gate, the power in not interrupted, it keeps strong. Obviously the gate is not operated when disconnected. When the pipe is reconnected, the power kangarooing starts again (if hot).

I'm wondering if I might have put the vacuum pipes on wrong!!!.. Duh! If I change the pipes over onto different connectors, will this cause damage?

Would you mind looking at the attached pic of the pipes and checking if they are right? The left red arrow shows what I think is the waste-gate, and the other red arrow shows where the vac pipe leads to. The left green arrow shows some other vacuum "spaceship" shape (please let me know what it is). The right green arrow shows where the "spaceship's" vac pipe leads to. This one is part of a three-way pipe connector.
 

Attachments

This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top