Problems running lean/rich - opinions on engine mods and how to solve problems

Daniel

I WILL be back...
Recently started clogging up a new member's thread by trying to sort out how to solve the problem of my faulty lambda sensor, and how to stop my car running rich. So thought I'd put up a new thread, so people can voice their opinions. I have included a list of current engine mods, and things to come.

Pipercross performance air filter
Pipercross cold air feed
Pipercross oil breather filter
1.3 fuel rail/injectors with fuel rail adapter
Walbro fuel pressure regulator
NGK iridium spark plugs
4-1 decat manifold
Custom 2" decat pipe
Ashley 2" midpipe
Jap style backbox, 2" bore with 4" outlet
Heatproof exhaust wrap from manifold to backbox
Completely removed aircon and remounted alternator

Planned mods - CG13 cams, ported and skimmed head, 2" downpipe, replace lambda sensor (currently disconnected as it's broken), NGK HT leads, ECU remap.

Let me know what you guys think.
 
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Daniel

Daniel

I WILL be back...
Orignal conversation between myself and gtsnissanb on Spike's thread:

Originally Posted by Spike11 - why is yours goin to fail lol

Because I have a 4-1 decat manifold, decat pipe (but no replacement cat), 2" Ashley midpipe, 2" Jap style backbox with 4" outlet, heat proof exhaust wrap from manifold to backbox, cone filter, 1.3 fuel rail/injectors, and a disconnected lambda sensor. It bangs like a shotgun on overrun or when I redline it because I've set my fuel pressure regulator to run slightly rich as well. I guess I'll have to find a friendly MOT garage that will "accidentally" put the sensor up the tailpipe of the car in the next bay

Originally posted by gtsnissanb - Why in the hell have you unplugged the lambda?? You don't want your car to run rich it looses power! Your not running anywhere near enough to need to worry about det! Your basically making your car slower, more polluting, #### on fuel?? Why not to mention the chance of bore wash, knackaring plugs, blocking up the exhaust! A car runs best at stoich you seem to be doing your up most to kill it

2 of the connectors on the sensor are broken, and I'm missing the seal that does inside it. Plus I think the rubber on the outside of one of the wires has snapped. Just haven't had a chance to replace it yet, so I've got no choice but to leave it disconnected. I only run it rich when I go to my local car cruises, just haven't had a chance to adjust is back. And I recently bought new plugs, so surely I don't need to worry about them? It doesn't feel sluggish at all

Originally posted by gtsnissanB - An overly rich car will not produce as much power as a car at stoich FACT you are most definitely not sucking in enough air to make the car run lean, so the fuel system mods you've made are just going to run it rich. Hence the popping on over run! You need the right AFR you can't just guess these things it only needs to be richer to prevent det. You won't have to worry about the plugs no if you don't mind changing them very regularly

Like I said, it only pops on overrun when I adjust the fuel pressure regulator. If I run it normally, it doesn't pop, and I actually get half decent mpg out of it. And as for spark plugs - I can get them for free, so I'm not worried about having to change them regularly

Originally posted by gtsnissanb - You obviously had a faulty lambda meaning you never had experience of it running right. You can't say unplugging the lambda will make your bone stock engine run better when all you have in the way of afr increase is the air box which the lambda would notice and alter the ecus fueling accordingly the mods you've done have taken the control away from the ecu which trust me knows better about fuel pressure and afr and now are running the car rich which is not good it's potentially deadly to a engine! Get it on a dyno get the AFR checked. I'm not being funny with you mate but things go very wrong with cars very fast I've built enough engines to know this. It makes me laugh as I've said in the past about the tards that stick resistors in their ect sensor, the Internet tells you more fuel=more power so you buy these things! But it's not the case there is more to combustion than fuel and go!

I'm not saying it runs better, but I did notice a slight change when I ran it with the lambda sensor uneplugged. When it was plugged in, it wasn't really sluggish in any way. Then it started to feal like it was running pretty lean, so I unplugged the sensor to check and make sure everything was ok with it. That was when I noticed one of the wires was snapped, and when I unplugged, I saw that 2 of the connectors were bent slightly. Tried to push them back, and they snapped. So now I have to run with it unplugged until I get a new one. I did think about putting an Almera airbox back in, but it feels like I'm getting more from my cone filter and cold air feed. I daresay I'll end up getting it dyno'd when I get 1.3 cams and skim the head, just to be safe, an maybe a re-map if I can afford it.

Originally posted by gtsnissanb - When the cams go in and the heads skimmed an increase in fuel will be more relevant. As running higher CR increases your risk of det so I'd imagine if you don't want to retard the ignition then your going to need higher octane fuel and more of it to keep it all cool and handle the longer duration and lift from the 1300 cams

Aha, so when I fit the cams, I'll need an increase in fuel anyway, which should make it run better? Along with maybe a second cold air feed, and running on 97 octane fuel instead of 95?
 

frank

Club Member
you,re banging your head against a wall fitting all those parts to a 1.0 tbh dan fwn, you,ve probably only gained about 8hp @ the topend, and probably actually lost hp @ around 2k rpm :eek:
and for the 10th time, 1.0 and 1.3 injectors are the same
 
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Daniel

Daniel

I WILL be back...
you,re banging your head against a wall fitting all those parts to a 1.0 tbh dan fwn, you,ve probably only gained about 8hp @ the topend, and probably actually lost hp @ around 2k rpm :eek:
and for the 10th time, 1.0 and 1.3 injectors are the same

But surely cams and head skim will solve this? Surely there must be a way to gain power from a 1.0l without turboing?
And ok, I give in, they're the same :(. Are there no bigger injectors that will fit the fuel rail?
 

frank

Club Member
But surely cams and head skim will solve this? Surely there must be a way to gain power from a 1.0l without turboing?
And ok, I give in, they're the same :(. Are there no bigger injectors that will fit the fuel rail?

yes you can easily get 80hp from a 1.0 (checkout baguete,s 1.0 blog) it would be great on the track with a close ratio g/box and 5:1 diff, but it not practical as a daily tho, no power below 5k and you have to rev the nuts off it all the time fwn
GA16 injectors will fit btw :)
 
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Daniel

Daniel

I WILL be back...
yes you can easily get 80hp from a 1.0 (checkout baguete,s 1.0 blog) it would be great on the track with a close ratio g/box and 5:1 diff, but it not practical as a daily tho, no power below 5k and you have to rev the nuts off it all the time fwn
GA16 injectors will fit btw :)

I rev the nuts off it all the time anyway, so wouldn't bother me at all :laugh:. And these are 1.6 injectors off an Almera?
 
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Daniel

Daniel

I WILL be back...
aye dan, black ones

See now I had a full set of them. Was going to fit them to mine, but thought it would just overfuel on a 1.0l and make it sluggish instead. Did I think wrong? Because I sold them to a mate for £10, and still owes me for them. Might ask for them back if they'll give me a bit more oomph :laugh:
 

Baz

Ex. Club Member
See now I had a full set of them. Was going to fit them to mine, but thought it would just overfuel on a 1.0l and make it sluggish instead. Did I think wrong? Because I sold them to a mate for £10, and still owes me for them. Might ask for them back if they'll give me a bit more oomph :laugh:

Do a search on the site man plenty of threads about changing injectors, fitting larger injectors alone will not give any extra power, no need for it, it'll just over fuel which means less power.
I know from experience as will a good few lads will tell you on here.As for the lambda, just fit a new one they are cheap
 
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Daniel

Daniel

I WILL be back...
Do a search on the site man plenty of threads about changing injectors, fitting larger injectors alone will not give any extra power, no need for it, it'll just over fuel which means less power.
I know from experience as will a good few lads will tell you on here.As for the lambda, just fit a new one they are cheap

I should be fitting a new one today, as long it gets delivered either today or tomorrow.

I know fitting larger injectors will just overfuel, hence why I didn't fit the 1.6 injectors. Then my fuel economy would just be non-existent. I could fill her up and the engine would just eat it in one big lump. Are there not any 1.2 or maybe 1.3 injectors that will fit, as the 1.0 and 1.3s on the K11 are the same?
 

gtsnissanb

Official MSC Trader
Lol bout freaking time
Told you I wasn't talking rubbish over fueling is not good for anything, your engine, wallet or environment and you can get a pretty big fine if a cop pulls you and does an exhaust test rarely happens but there you go
Bigger injectors are a waste of time without supporting mods and unless your fuel system demand more fuel you won't need them! I'm not sure what duty cycle the stock ones are running on yours but I'd imagine they can easily cope with the minor bolt on mods, as can the fuel pressure! Tweaking these at your current spec is most likely gonna loose power as the ecu should cope fine providing you fit a new lambda
I doubt you'd need bigger injectors for the cams and skim tbh just higher octane fuel to cover the det risk so you don't melt a piston! Bigger injectors are required when the stock ones are close to the max duty and I doubt the extra fuel the planned mods need will max the stocks (I may be wrong as i don't know what they run as standard but I know for around 80bhp extra on my sr the stock squirters are fine)
I'd imagine you will only need bigger squirters when you force induct it as I can't imagine the AFR will dramatically change enough to warrant the bigger cc injectors
I pretty much don't need to add anything else to this as all my previous posts are up there lol
 
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Daniel

Daniel

I WILL be back...
It feels like I'm being ganged up on here :laugh:. New lambda sensor turned up about 15 minutes ago, so that will be getting fitted today (as I said before, I had to run with it disconnected because it was broken, I had no choice!). How much will a wide band o2 kit and gauge cost? I'm trying not to spend big £££££ here.

And Shaun, I might be dropping a 1.3 lump in there, as I might have sourced a low mileage donor engine. However, I need to make sure it isn't seized. If it is, I'll just wait until I get an SR, as I want to get one to work on anyway.

Karl, I will be keeping the box if I drop a 1.3 engine into her. The gearbox was replaced shortly before I bought the car, so I daresay there's not much point in replacing it - and aren't the 1.0l gearboxes the same as the 1.3s, just with a lighter flywheel?
 

Baz

Ex. Club Member
Id imagine if the sensor was broken , connected or disconnected would make sweet FA of a difference, the ecu is STILL getting no signal as to whats going with fueling. Sorry Im know I sound thick through my posts but I'm only telling the truth. You need to do a bit more research on modifying engines because you may have the basics but even the basics can be wrong
 
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Daniel

Daniel

I WILL be back...
Id imagine if the sensor was broken , connected or disconnected would make sweet FA of a difference, the ecu is STILL getting no signal as to whats going with fueling. Sorry Im know I sound thick through my posts but I'm only telling the truth. You need to do a bit more research on modifying engines because you may have the basics but even the basics can be wrong

I felt a bit of difference, unless it was a mind thing. We'll find out when I fit the new sensor :grinning:. I did a bit of research, but clearly not enough. I'm going to be doing a lot more research when I get an SR, as I want to convert it to run on bike carbs - I certainly don't want to be getting that wrong :laugh:
 
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Daniel

Daniel

I WILL be back...
Why An SR? Super S' are just as cheap...

I prefer the interior trim in the SR, and don't want to have to swap interiors with someone. Plus I want a black pre-facelift 1.3, and didn't think the Super S came in black?
 

gtsnissanb

Official MSC Trader
Id imagine if the sensor was broken , connected or disconnected would make sweet FA of a difference, the ecu is STILL getting no signal as to whats going with fueling. Sorry Im know I sound thick through my posts but I'm only telling the truth. You need to do a bit more research on modifying engines because you may have the basics but even the basics can be wrong

Depends how it's broken mate unplugging it sticks it in rich mode to save the engine, if somehow the lambda is sending the wrong signal it can cause damage to the engine! Ie if its telling the ecu the engine bone cold it will run as if it in the enrichment stage, whereas when its unplugged it returns to a safe default fuel map.
But as the wire was broken in this instance I believe there would have been no difference as this wasn't a dodgy sensor it was effectively disconnected :) most probably a mind mind thing

Let me also add running richer than stoich is not a bad thing, under acceleration but only just richer not mega rich as this most likely will be
On idle and cruise rich is bad, poping flames is a sure sign of richness as the engine can't use all the fuel so it's getting binned through the exhaust which most likely cause damage an is not legal!
 
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Daniel

Daniel

I WILL be back...

Aha :grinning:. Shame it was 5 years ago though, £300 for a car with 40000 miles isn't bad. But even so, I prefer the interior of the SR. And yes, while I will be stripping it out completely (eventually) and fitting 2 bucket seats and a roll cage, I will have to keep the interior in until I can sort it out properly. Plus if I decide I don't like not having an interior, I need something I like to put back in.

Depends how it's broken mate unplugging it sticks it in rich mode to save the engine, if somehow the lambda is sending the wrong signal it can cause damage to the engine! Ie if its telling the ecu the engine bone cold it will run as if it in the enrichment stage, whereas when its unplugged it returns to a safe default fuel map.
But as the wire was broken in this instance I believe there would have been no difference as this wasn't a dodgy sensor it was effectively disconnected :) most probably a mind mind thing

Let me also add running richer than stoich is not a bad thing, under acceleration but only just richer not mega rich as this most likely will be
On idle and cruise rich is bad, poping flames is a sure sign of richness as the engine can't use all the fuel so it's getting binned through the exhaust which most likely cause damage an is not legal!

Don't worry people, I've now connected the new lambda sensor, and set up the fuel pressure regulator so it's running just right. Dosn't pop at all now, only if you really rag it (and only then do you get a little baby pop with no flames). Doesn't feel sluggish or anything, and actually feels a little bit smoother. So hopefully that's solved it until I get a bigger engine (Y)
 

gtsnissanb

Official MSC Trader
Aha :grinning:. Shame it was 5 years ago though, £300 for a car with 40000 miles isn't bad. But even so, I prefer the interior of the SR. And yes, while I will be stripping it out completely (eventually) and fitting 2 bucket seats and a roll cage, I will have to keep the interior in until I can sort it out properly. Plus if I decide I don't like not having an interior, I need something I like to put back in.



Don't worry people, I've now connected the new lambda sensor, and set up the fuel pressure regulator so it's running just right. Dosn't pop at all now, only if you really rag it (and only then do you get a little baby pop with no flames). Doesn't feel sluggish or anything, and actually feels a little bit smoother. So hopefully that's solved it until I get a bigger engine (Y)

If your running no cat it probably will still pop a little on overrun from a heavy right foot session
 
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Daniel

Daniel

I WILL be back...
If your running no cat it probably will still pop a little on overrun from a heavy right foot session

It does pop a little bit, but you really have to rag it hard or blip the accelerator when you change down. Apart from that, it's all good (Y)
 

gtsnissanb

Official MSC Trader
It does pop a little bit, but you really have to rag it hard or blip the accelerator when you change down. Apart from that, it's all good (Y)

If it's been running rich for a while I'd get the plugs out and give them a clean they'll most likely be coked up maybe check and increase the gap a tad if the ignition system can handle it, my old ls400 I increased the gap and found the car was a tad more peppy, I then got bored and cut the plug and there was a definate difference! and maybe a nice long run on high octane fuel to give it a nice internal clean
 
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Daniel

Daniel

I WILL be back...
If it's been running rich for a while I'd get the plugs out and give them a clean they'll most likely be coked up maybe check and increase the gap a tad if the ignition system can handle it, my old ls400 I increased the gap by .06 and found the car was a tad more peppy! and maybe a nice long run on high octane fuel to give it a nice internal clean

That was going to be the next thing to do, once this rain stops. I've got a spare set of iridiums in the garage somewhere, so if they're way too coked up, I'll just change them. I need to fill up tomorrow as well, so I'll probably fill up with BP Ultimate or Shell Optimax. It's only an extra 5p per litre round where I live, so I won't end up paying much more than I do already (Y)

And how can I check and/or increase the gap? I wasn't even aware you could :wasntme:. And what do you mean by cutting the plug as well?
 
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