S13 Losing power under boost?! Help!

[jackmcinally]

Hey Guys!

I just got my first S13 the other week, and I've noticed that it seems to be losing power in boost, rather than gaining it.. Obviously something is wrong - can anyone shed some light on this? (please tell me the turbo isn't gone! ) It has a known exhaust leak coming off the turbo, which is being fixed on Monday.. I'm hoping this is the issue, but I have no idea.

This is also my first turbo car, so apologies if I'm not totally clued up!

Mods:
FMIC
Garrett T28BB (no boost controller, running wastegate)
Uprated Fuel Pump (Walbro)
Full 3" Turbo-back Exhaust
Pod Filter

[pointz]

Leak between mani and turbo will cause boost to fluctuate as will a boost leak!

You should get a stage 2 h-dev chip in there and a boost controller as you have the rest of the spec required.

[dukey]

Is it a lambda model as could be showing to much 02 on sensor if exhaust leak is bad and set it to limp. You getting engine lights?
You aware of any boost leaks

[pointz]

Also do a ecu diagnostic check to see if it has registered any faults.

Search "ecu diagnostics" in tech s13

[jackmcinally]

Cheers guys! I'll try and check for boost leaks in the morning H-Dev stage 2 chip is the next thing I plan to buy :P I'm not sure if it's a lambda model, how would I check this? I'll have a look at how to check the ecu too! Thanks for the replies!

[jackmcinally]

Also, there are no warning lights

[pointz]

What year is it mate? Prefacelift = non lambda Facelift = Lambda.

Get that gasket replaced would be my 1st priority tbh

[jackmcinally]

It's an early 1991 (pignose)

[jackmcinally]

Wait a minute.. I have a stage 2 ecu already, which I assumed was knackered, because I plugged it in and it ran like absolute garbage. But that ecu has '02 sensor' written on the back, so I'm guessing that's from a facelift S13. How could I go about getting a lambda sensor put on my car? Or should I just get the chip swapped from that ecu, to my one?

[pointz]

Have a look at where the exhaust attaches to the turbo, if it has lambda it will be on the elbow if not it will have a bung!

If it is non lambda you will need a non lambda socketted ecu to put your chip into!

[dukey]

Do you need the afm too as it's different?

[pointz]

Yea 3 pin for facelift
4pin for pre facelift

Seeing if it has lambda to determine whether it has prefacelift or facelift ecu/wiring etc as i believe 1991 was when some of the cars wer going over to facelift!

[Dastardly]

My 1991 has no lambda.

[pointz]

My 1991 has no lambda.

I could be wrong i don't remember exactly when they started going from pre-facelift to facelift!

[skyshack]

Check the turbo. Take the AFM trunk off the inlet and then take hold of the compressor nut. Try to pull it in and out and side to side. There should be very little movement. Give the nut a flick to spin the shaft, it should spin easy without any trace of blades touching case.

Does it just fade or is it like a brick wall?

Fade is likely to be fuel related. Power supply to pump needs to be checked for voltage drop. Could have sliced the fuel line when replacing something? Filter or pump, this restricts flow, worse on outlet as the sliced bit curls to block flow more.

Brick wall, ECU fuel cut needs a chip.

Swap the chip. Swapping to a Lambda requires a turbo dump pipe with threaded boss. The loom has co-ax shielded wire for Lambda, 2 wires for Lambda heater. Swap passenger side engine loom for a face lift one but that will have 3 pin AFM plug so 3 pin AFM needed to avoid splicing loom.

[skyshack]

I could be wrong i don't remember exactly when they started going from pre-facelift to facelift!

First series 0 was made Jan 1988 batch of 13, only 31 made by end of Nov 88. Dec 88 was first month of full production, 501 cars made. Last pre-facelift series 0.0 was made Aug 1989.


Last pre-facelift series 1.0 was made Aug 1990. Only 6 made July-Aug.


First 2.0 series "facelift" was made Nov 1989. Very few made during 1990. The ones made at end of 1990 would have been shipped for press test cars and dealer preview. 522 in Jan 1991. Last series 2.0 was Sept 1991 (just 9 cars). It would have taken about 6 months for them to arrive at the dealer. So Facelift should be reg in UK mid 1990. If you find one reg before that it's part of the test fleet.



Series 2.2 (there was no 2.1, should have been around Aug/Sept 92) started Sept 1991, ended Sept 1993.
There were only 9 cars made between Sept 92 and end of Nov 92. Sept is when Nissan usually rolls over the new model so something else was using all the build track(s).
Series 2.3 started Sept 1993 (Not sure if this is proper "series" as chassis numbers just rolled over to 230000 but it was around the Japanese model change month of Sept) and last was made Dec 93.

[pointz]

Very interesting info there i'm going to have a look at the exact reg date of mine later to see which batch is made in!

[Dastardly]

I shall look at mine too later. I have 2 pre-facelifts registered 1990 and 1991. Must have hung around in showrooms?
Just remembered my chassis number of my 1991 car is U01. Sorry for the thread hijack.

[jackmcinally]

I'll check for an o2 sensor after work and report back. It's an H reg, so that's 1991. But I thought you could tell facelift from pre-facelift by the front bumper? Mine has the 'pig nose' and cheers for the advise on checking the Turbo, I'll see if I can check for play and such after work too! When it comes on to boost, it just doesn't seem to gain any power from then on, just kinda stays the same. Not a violent kinda stop, just doesn't gain any power. If anything, it loses power. I had a fuel problem before, but we traced that to the fuel pressure regulator, and got a new one in - also changed the fuel filter at the same time, and checked that the fuel pump was working correctly.

[pointz]

Timing set correctly? Worn cas splines or broken locator peg maybe