Intercooler gone?

[fattail95]

Hi guys,

When looking at Peugeot Planet the other day, I noticed that my turbo pressure measured is consistently ~200mb behind the turbo pressure reference value, however it can and will hit the full ~2000mb pressure limit under load, and it does pull very well. Does this mean I have a boost leak? I've noticed at the bottom of the intercooler, there is a fair amount of built up oil, and on the left hand side (as you look at it from the bonnet) there is slight bubbling when the engine is revved and under boost. Does this signify a leak, and is this leak big enough to cause the ~200mb deficit on boost?

I've also noticed that at idle, the turbo pressure measured is almost always the same as atmospheric pressure, ~1035mb. I was told by someone that an HDi 110 should generate ~1200mb on idle, which it doesn't. Again, is the intercooler leak accountable for this?

Many thanks!

Benjamin

[Rolebama]

Two thoughts. Bubbling can only mean a leak, and why would you want turbo boost at tickover? On my DT it used to come in at about 2000rpm when accelerating, but cruising at 70mph, my boost gauge only showed 1lb of boost. 2000mb is approx 30lb, and I would think that a bit high for a 'standard' setup. My DT was only rated as 14/15lb from the production line.

[PeterN]

Turbo pressure is dependent on exhaust gas flow which is dependent on engine output, it could be that you are down on power, 1st suspect is the MAF. It sounds as though you have a slight leak but I wouldn't think enough to affect the boost pressure.

Peter

[fattail95]

Turbo pressure is dependent on exhaust gas flow which is dependent on engine output, it could be that you are down on power, 1st suspect is the MAF. It sounds as though you have a slight leak but I wouldn't think enough to affect the boost pressure.

Peter

MAF was replaced 2 months back with an OEM Siemens part, and Planet confirms its functioning as intended. It has been remapped, and builds full boost at approx ~2000rpm. It doesn't feel slow, but I was wondering why the measured value is behind the reference value?

[fattail95]

Two thoughts. Bubbling can only mean a leak, and why would you want turbo boost at tickover? On my DT it used to come in at about 2000rpm when accelerating, but cruising at 70mph, my boost gauge only showed 1lb of boost. 2000mb is approx 30lb, and I would think that a bit high for a 'standard' setup. My DT was only rated as 14/15lb from the production line.

The 2000mb figure includes atmospheric pressure, so its approx 1000mb of boost, or 15psi over atmospheric. I didn't think there would be any boost at idle, but someone (cant remember who) said there should be 1200mb at idle (or ~3psi).

[Doggy]

I think that was probably me. It was based on something I noticed when monitoring engine parameter measurements on someone's 2.0 HDi last year - unlike 2.2's, (which always indicate approximately atmospheric pressure at idle), this one showed around 1200 mbar, which I assumed was normal for the fixed geometry 2.0 turbo.

On reflection it could have been a 90, (which also has a mechanical wastegate).

I'll double check next time I have pp2k hooked up to a 110, (unless one of you 110 owners let's us know first).

[fattail95]

One thing I've noticed when its hooked up to Planet is that atmospheric pressure is always stated as 1035mbar. Never changes. I assumed the atmospheric pressure was read by reading the pressure from the MAP sensor before engine startup. Could this indicate a potentially faulty MAP sensor? I looked at my friends 2.2 the other day, and his read 1017mbar, but mine never strays from 1035mbar.

In terms of the wastegate, I think its very likely that the ECU on the 110 has it fully open to prevent any boost being built, perhaps to prevent it using more fuel when idling, vs the mechanical wategate?

[Doggy]

One thing I've noticed when its hooked up to Planet is that atmospheric pressure is always stated as 1035mbar. Never changes. I assumed the atmospheric pressure was read by reading the pressure from the MAP sensor before engine startup. Could this indicate a potentially faulty MAP sensor? I looked at my friends 2.2 the other day, and his read 1017mbar, but mine never strays from 1035mbar.

The atmospheric pressure sensor is built into the ecu.

In terms of the wastegate, I think its very likely that the ECU on the 110 has it fully open to prevent any boost being built, perhaps to prevent it using more fuel when idling, vs the mechanical wategate?

Very possibly - as I said the figure of 1200 mbar at idle may well have been from an HDi 90.

[fattail95]

With regards to the intercooler, does the oil residue and bubbling mean it need replacement?

[fattail95]

@Doggy

I hooked up another working 110 to PP2000 the other day, and it displayed atmospheric pressure at idle, so it must be a 90 thing

[Doggy]

I reckon you're right. It may also help explain why 90's don't seem to have much turbo lag.