Still problems!!!!!!!!!!!!!!!!!!!!!!!!!!!

[REBEL GT TURBO]

Right! Still having problemssss!

Car runs perfect, starts perfect, totally reliable over last 15months since buying it!
Had problems with it running lean from day 1!
Got an aem afr fitted reads 14.5 on tick over from cold sticks on this tho even on boost? It drops to 13.6 after a short run! It also goes into red 16/17 sometimes when on boost then goes back over to 14ish as the boost rises!
So I now running it back on the t2 with standard 8psi boost!

I've fitted new:
fuel pressure regulator
Fse racing fuel pump
Fuel filter
Carb (standard jets)

Removed fuel filter in carb
Cleaned fuel filter in tank sender

I've now been told it could be:

Timings out?
Enrichment jet problem?
Major boost leak?

I need a proper
Mechanic ASAP now!!!
Anyone local to Manchester that's free this week or weekend??

Thanks guys

[Tony Walker]

You have a picture of how your sensor is fitted?
Blowing exhaust/manifold gasket turbo elbow?

[REBEL GT TURBO]

Hi tony it's welded to the exhaust about 5inches from the turbo elbow!

[Brigsy]

Try a different wideband to confirm the readings?

[REBEL GT TURBO]

Try a different wideband to confirm the readings?

It's reading perfect because you can feel the engine doing what the afr is reading, if it goes into red say 16/17 I sometimes get back fire which will be detonation! It's def not the wideband!

[Tony Walker]

kinda sounds like its hesitating coming on boost? 1st stage blocked?

[REBEL GT TURBO]

kinda sounds like its hesitating coming on boost? 1st stage blocked?

I can't see it being the carb as I've changed it! And saw the carb running on the other car! I can't see 2 different carbs giving me the same problems! I just want it sorting now! The car looks like a 10 second car but its not going like one!
I need to get it running right in standard form so I can fit my gorgeous turbo and set the carb for 17psi!

[Tony Walker]

Aei possibly? incorrect ignition timing causing unburnt oxygen

[REBEL GT TURBO]

Aei possibly? incorrect ignition timing causing unburnt oxygen

Do you have a workshop tony? The aei unit is new tony I'll check it'

[Renault 5 GT Turbo]

You have a picture of how your sensor is fitted?
Blowing exhaust/manifold gasket turbo elbow?

I'd second this, get a new gasket on there. Not expensive and can then be ruled out. Spray some carb cleaner around the inlet/exhaust manifold area. If the revs change you will know the gasket is at fault.

[REBEL GT TURBO]

Checked the aei unit tonight, put 20psi on it and it held it! Going to fit an inline fuel pressure gauge (cockpit) mounted to see what pressure I'm getting on/off boost! Is it right that it should be 2psi over boost level? So 8psi boost 10psi fuel? What should it be off boost? Also check for air leaks with so carb cleaner at the carb and turbo elbow!

Thanks guys.

[Dave Reed]

Checked the aei unit tonight, put 20psi on it and it held it! Going to fit an inline fuel pressure gauge (cockpit) mounted to see what pressure I'm getting on/off boost! Is it right that it should be 2psi over boost level? So 8psi boost 10psi fuel? What should it be off boost? Also check for air leaks with so carb cleaner at the carb and turbo elbow!

Thanks guys.

What boost are you trying to run? As you said you've gone back to standard boost.

What FPR did you fit? Is it piped up correctly?
Fuel pressure should be around 5-6psi on tick over, it should stay this way as the boost builds ie 10psi boost, 15-16psi fuel pressure etc.

just to add to this, make sure that your boost reference pipe to the FPR isn't damaged/split

[REBEL GT TURBO]

I'm trying to run standard boost! And the fpr is a genuine Renault one! It's getting 5 psi at tick over ATM so that's correct!!

It must be something to do with the carb!

Ive now ruled out the:
Fuel filter
Fuel pump
Fpr
Fuel sender filter
Aei unit
Small vac hoses (all new)

So I think it must be a boost leak somewhere!!!

[REBEL GT TURBO]

One other thing is the idel screw! I've been told it only needs around 3/4 turns from closed and this should do it! I've had to turn mine like 8/10 times for it to idle correct ie not lumpy!

[Dave Reed]

One other thing is the idel screw! I've been told it only needs around 3/4 turns from closed and this should do it! I've had to turn mine like 8/10 times for it to idle correct ie not lumpy!

Ok so it sounds like u've checked every thing..
You say the idle screw, do you mean the mixture screw? If so your afr gauge should change? Out should be leaner, in more fuel.. Although this shouldn't affect on boost fueling too much.

Is the carb fuel feed connected to the carb correctly? Are you 100% the boost reference pipe is connected to the correct carb outlet?

Only other thing to check is the accelerator pump, is it moving freely?

[tubbyG]

did you replace the carb base gaskets when you swapped the carbs over, or re-use the old ones??

[Renault 5 GT Turbo]

I'd second this, get a new gasket on there. Not expensive and can then be ruled out. Spray some carb cleaner around the inlet/exhaust manifold area. If the revs change you will know the gasket is at fault.

I still reckon it is the manifold gasket. Hard to spray the underside of inlet to test for a leak. If you replace carb gasket and manifold gasket if problem still exists then it would point to a split boost hose.

[REBEL GT TURBO]

did you replace the carb base gaskets when you swapped the carbs over, or re-use the old ones??

Reused old ones!

[Tony Walker]

Boost hose doesnt effect fueling. the fueling is determined by the flow through the carb, any leak before the carb makes no difference.

[Tony Walker]

Your intial post is a little confusing. just clarify it a little.
Say your in third gear about 2000rpm whats your afrs? they will vary depending on load and rpm but roughly.
Then foot to floor what happens, fueling should initially go a bit crazy should be slightly rich off the accelerator jet then you should be on boost and what afr is this and does it change as the rpms build? what is the afr full boost at say 5500 ish?

[LYNCHSTAR]

Mine kept on leaning its head off once big style i just changed the carb base gaskets then it was ok you can get a set from cgb about £3 for a set of two. some times its best to blob the mixture screw with silicone aswell.

[REBEL GT TURBO]

Your intial post is a little confusing. just clarify it a little.
Say your in third gear about 2000rpm whats your afrs? they will vary depending on load and rpm but roughly.
Then foot to floor what happens, fueling should initially go a bit crazy should be slightly rich off the accelerator jet then you should be on boost and what afr is this and does it change as the rpms build? what is the afr full boost at say 5500 ish?

3rd gear 14.2 afr if I boot it it shoots round to 16/17 for a bit then back to 14ish! Sometimes it will just stick on 14.2 when I boot it! If that makes any sense?

Yeah it goes up as rpm's build!