Boosting issues when hot

[Tjp8]

Recently as the car gets hot after a few hard pulls it stops boosting properly and it pulls back when i accelerate and then pops,

Falls flat on its face when i get to around 0.5 on the boost gauge , feels like hitting a wall and like it doesnt really want to have any boost at all.

Thought it might be a blocked main cat.

Bar the boosting and pulling back at the moment the engine is idling fine, not over heating, had an oil change within the last 1k miles. And is driven daily .

Any thoughts on what issue this maybe .

Thanks

 

[jdmr_neil]

Single or twins?
Ecu?
@0.5 bar does it just stop boosting or physically halt the car like fuel cut.

Id be more inclined to look at plugs tbh, when we're they last changed

Fuel filter?

 

[Tjp8]

Fuel filter was new last year, new fuel pump and sock, new plugs less then 2k ago.apexi ecu mapped by jaydee and stu at 1 bar.

Its on twins sequential twins.

It feels like fuel cut, itl halt the car and buck and pop until i let off and gentle accelerate.

It Had between quater and half tank of fuel at the time.


Its strange cos i drove it this morning and it was fine and even half way to my destination tonight it was fine and pulling strong. Then i was about 45mins into a steady 60mph drive and it just wouldnt boost anymore and bucked and popped even when i got into the slower speeds after it did the same issues .

Thanks
Tj

 

[JoeLanger]

Hose popped off the waste gate? Isn't 0.5 bar spring pressure on twins?

 

[Tjp8]

Hose popped off the waste gate? Isn't 0.5 bar spring pressure on twins?

Ive checked hoses last night when i got home and didnt see anything unusual , car drove perfect until i did a hard pull, it boosted fine then after i started slowing down it wouldnt boost and started stuttering again.

Its strange like once some real heat gets into it it doesnt want to know any boost

 

[Ceylon]

Sounds like solenoids to me, when they start to go they usually pass tests cold but fail hot.

 

[Tjp8]

Sounds like solenoids to me, when they start to go they usually pass tests cold but fail hot.

Could it be any solenoid in particular? Il take the upper inlet off and have a little look.

 

[Ceylon]

Sorry just re-read the first post, If leads and plugs are ok then I'd check the coils are in spec if it feels like hitting a wall. Easy test with a multimeter. Ignore my solenoids comment, I only scanned through the highlights pre my morning coffee .

 

[Tjp8]

Sorry just re-read the description, If leads and plugs are ok then I'd check the coils are in spec if it feels like hitting a wall. Easy test with a multimeter.

Leads are about 7k old, plugs are less then 2k.

Im assuming the coils are original and are on 38k odd.

How would i test them, i do have a multimeter to hand.

Thanks

 

[Ceylon]

 

[jdmr_neil]

Sounds like a ht lead is pulling away from the plug after that hard pull. When you have that issue next, stop and get your hand down there. Give all the leads a good shove into the plug and if you feel a little click on any that's your problem.

Try again and if it still happens you need new leads.

This can happen to relatively new aftermarket leads and often on fake branded leads.

 

[cib24]

What leads do you have? Nothing beats the factory NGK leads.

 

[Tjp8]

Sounds like a ht lead is pulling away from the plug after that hard pull. When you have that issue next, stop and get your hand down there. Give all the leads a good shove into the plug and if you feel a little click on any that's your problem.

Try again and if it still happens you need new leads.

This can happen to relatively new aftermarket leads and often on fake branded leads.

Just checked the leads they are snug both sides.

 

[Tjp8]

What leads do you have? Nothing beats the factory NGK leads.

I had some custom made by a company when i first bought the car years ago, not too sure what company it was now.

 

[cib24]

Does the car still Rev out to redline even at the lower boost level?

 

[Tjp8]

While driving it wont rev out at all when its acting up.

Just pulled the coil side of the leads and a few of them are corroded , im just testing the coils now

 

[Tjp8]

View attachment 27507

I did the test on trailing on the a-b and a-t and im getting 0 ohms on both

 

[Ceylon]

Sounds like your multimeter is on the wrong setting, you should get readings higher than 0 for the coil winding. However, the A-T connection should never show to have continuity so if it does like you say then that coil is toast.

 

[Tjp8]

Sounds like your multimeter is on the wrong setting, you should get readings. However, the A-T connection should not have continuity so if it does then that coil is toast.

I did the same tests on the leading coil and i got reading but both trailings im getting 0 on both

 

[Ceylon]

Got a pic of your multimeter showing what it's set to? A to T should always show now continuity if the coil is in spec.