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I had new plugs put in when the engine was changed, and I'm told they are fouled and needed cleaning already. I'm just trying to pinpoint the problem, I'm currently fighting with the guy I got the engine off, but I'm starting to wonder if it is a fuel problem after all.
Hello,
Yes it could be a fuelling problem.
The emissions report means one (or more) of the following:-
- there is too much fuel going in
- there is not enough air going in
- the mixture isn't being combusted properly
- the cat is knackered.

If number 1 it could be the injector(s) leaking too much fuel in, so that's why the plugs will be fouled, and they will be again now!
But be aware that too much neat fuel for too long will badly affect the lambda probe and the cat, so it's difficult to separate cause and effect.
 

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Super fantastic Mod Technical Supremo Nice Guy
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ok your oil is tucked for 1

you have no air going into the engine

so whats the engine temperature sensor actually reading .
as this looks like its still on choke from these readings

Does it idle ok, or is the engine revving up and down
two engines are not going to be the same
whats come off your original engine , and been fitted to the donor
any ideas on this


but
I would be saying Lambda is tucked on that,
is this the lambda that was on original exhaust,
who fitted the exhaust

Disconnect Lambda ( Top One ) and see if engine sounds better


is engine management light on?

I know its not a failure being on, on the year of vehicle but is it
 

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Discussion Starter · #23 ·
ok your oil is tucked for 1

you have no air going into the engine

so whats the engine temperature sensor actually reading .
as this looks like its still on choke from these readings

Does it idle ok, or is the engine revving up and down
two engines are not going to be the same
whats come off your original engine , and been fitted to the donor
any ideas on this


but
I would be saying Lambda is tucked on that,
is this the lambda that was on original exhaust,
who fitted the exhaust

Disconnect Lambda ( Top One ) and see if engine sounds better


is engine management light on?

I know its not a failure being on, on the year of vehicle but is it
Thank you.. I will answer the best I can. Bear in mind I haven't seen the car since the engine was put it. The oil is new, was changed when engine put in as the engine was dry. Last time I drove it was in between the old engine and this one, it was up and down on revs. He did have to use some parts off the old engine but not sure what, not much though. He was planning to change the lambda with the exhaust, it would be daft not to, I will ask if he did. The engine light is not on, but I wouldn't be surprised if these didn't work. Are you saying this is likely to be something rather than the engine?. Apparently there is blue smoke on start up especially but it's been for a run today between garages for second opinion and is not as bad. Thanks for your reply
 

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Super fantastic Mod Technical Supremo Nice Guy
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So you are burning oil then
Or is this only on starting first thing after standing overnight
How much blue smoke are you on about

Can we ask How long before it clears
 

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Discussion Starter · #25 ·
So you are burning oil then
Or is this only on starting first thing after standing overnight
How much blue smoke are you on about

Can we ask How long before it clears
It's only after standing overnight, it's not a massive amount and clears to the eye after a minute or so, both mechanics think it's the valve seals as the car it came from hasnt had an Mot for 3 years, and has pretty much the same mileage now as it had 3 years ago, so might have just been sitting around. So they are sort of hoping it might get better as it runs it, but from what I'm hearing there must be other issues apart from the engine?
 

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Discussion Starter · #26 ·
Forgot the say I think the temperature sensor is OK. It's always started at 1400 revs and works its way down to 750, even after the problems started
 

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Discussion Starter · #28 ·
I will give my mechanic his due on that one, he did 2 days ago, all running at 125 I think he said, all fine anyway. The previous engine had 1 at 50 and the other 3 at 150.
 

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Super fantastic Mod Technical Supremo Nice Guy
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would be looking closely at the lambda here,
Dont think the heater part is working myself
Would be saying the heater element is tucked, and chances are this is when it came out of old exhaust and put in new


All those dodgy readings can be put down to a lambda issue
 

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Discussion Starter · #30 ·
would be looking closely at the lambda here,
Dont think the heater part is working myself
Would be saying the heater element is tucked, and chances are this is when it came out of old exhaust and put in new


All those dodgy readings can be put down to a lambda issue
I'm not the brightest at this stuff but even I would have changed the lambda, haven't had a reply off him yet. He did say he was going to. Its probably nothing but I did put e10 fuel in by mistake. This caused me a lot of starting problems, had to use easy start a few times, eventually the shell v power I was putting in coupled with a new battery solved the problem, don't know if it could have damaged the fuel system though, I mean I do very few miles in the car
 

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The previous engine had 1 at 50 and the other 3 at 150.
That says it was worth swapping engines.

Also says it doesn't necessarily come down to something common between the two engines, someting that moved from A to B.
It could easily be a new problem.
Ourkid reckons Lambda and he is always worth listening to.
Something like PCV letting too much from crankcase...if it is the old PCV valve could be blocked.
Coolant temp sensor.... Ourkid said it earlier, could be running on choke
Leaky inlets so too rich but HC seems high for that
Similar if coils are playing up, would get high CO but HC seems high.
 

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Discussion Starter · #32 ·
That says it was worth swapping engines.

Also says it doesn't necessarily come down to something common between the two engines, someting that moved from A to B.
It could easily be a new problem.
Ourkid reckons Lambda and he is always worth listening to.
Something like PCV letting too much from crankcase...if it is the old PCV valve could be blocked.
Coolant temp sensor.... Ourkid said it earlier, could be running on choke
Leaky inlets so too rich but HC seems high for that
Similar if coils are playing up, would get high CO but HC seems high.
Sorry for the ignorance but what is the PCV.
 

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Pressure Control Valve
Controls crankcase breathing into the inlet.
Should only let fumes in at higher revs when they have less of an impact on emmissions
Clogged or broken and they can let too much in even suck fumes out of the crankcase.... fairly common cause of high HC values
 

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Discussion Starter · #35 ·
I appreciate all of the answers you are all giving me, it's all very helpful. Could I just ask one more thing, if there is blue smoke from the car that is definitely due to the engine?. There is clearly other problems with the car, but blue smoke is definitely an engine burning oil?
 

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Yeah, common wisdom says oil is blue smoke but wanna put a bet on it.
But can be little difference to colour with overfueling.
I tend to work more on smell but that is more difficult to describe.... coal burning sort of smel for oil, fuel smell for overfueling.
Typical causes..oil.... bu55ered rings or worn bores, not with those compression values, old oil (you said it was new) valve stem seals... at 39K (if mileage to be believed), PCV, clogged air filter.... at least you haven't a leaky turbo to worry on.

It's pick on most likely, diagnostics can help here, live data.
Is the Lambda reading moving?
What temp is the engine running at.
Fuel trim values
Any error codes?
 

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Super fantastic Mod Technical Supremo Nice Guy
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Pre OBD and not many scanners will Actually read live data

Only really know 1 for Renault on that year
CC
 
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