danny951

alright.. as per the request of many here on rennlist and even by Don Istook, I had clamped off my CV to Wastegate line to basically test my wastegate/turbo.. well I still got low boost, but today I decided to try it again just to be certain and clamped my crescent wrench down even further, until it would barely clamp down on the hose... then drove around and what do ya know? FULL BOOST! I pegged out the boost gauge and I'm smiling ear to ear!

so now (after pm'ing those who have been gratiously helping me out) I just wanted to let everyone know, in case someone else reads this and has a similar problem..

I am guessing that the culprit, then, is my cycle vavle and I can just do a delete and run an MBC. I asked special tool already, but anyone have a write-up for bypassing the CV altogether and using a MBC such as reliaboost? I'm assuming simply hooking up the reliaboost does not fully bypass the CV.

NZ951

There are tons of write ups about installing an MBC including diagrams etc...

Dal Heger

I wouldn't get rid of your CV. If it's limiting boost to 1.2 bar then there is something wrong with the car. I'm guessing that it's hearing knock and limiting boost to save your engine.
This is the way that the KLR and DME work together to control knock. The knock sensor mounted on the head "hears" knock. First the engine management will pull timing back to see if that helps. If it still hears knock then it will limit boost to 1.2 bar (absolute) in an attempt to control the detonation. If that helps, then it will slowly add boost back and timing until it hears knock again. This is a feedback device for the engine.

Since these engines do not have "check engine" lights then the only way you'll know something is wrong is by the boost gauge. If you are consistently only getting 1.2 bar then there is something wrong. If you have ruled out the vacuum hoses (which you have by clamping the wastegate line shut) then you have to troubleshoot the rest of the system. My guess is that you are getting knock and the engine management is controlling for it by limiting boost (thereby keeping your engine alive).

I hate removing the CV for this exact reason. You will get rid of the symptom (the engine will run great with 1.7-1.8 bar) but you risk blowing a headgasket or burning a hole in the cylinder because you did not get rid of the problem.

Figure out why the engine is limiting boost. What is the cause?

Run your car hard, then before turning it off, read the blink codes. If you turn it off it erases any codes it found. Assuming it limits the boost to 1.2 bar, then you should get a blink code that will lead you to the cause (or at least narrow it down).

Dal.

danny951

yeah, that makes sense about the CV.. so I drove it around hard and the master caution even came on several times while making more than .2 bar of boost and under hard acceleration, but when I got home (left the car on) and plugged in my fault code reader, I got no blinks.. I checked the led on the batter and it works fine, but I get no blink codes. Also, after I got home and left the car on, the idle was still very smooth (and I told you on the phone that it idles at 1100-1200, but that is wrong, after I let off the gas, it pauses at 1100-1200, but then settles down to around 900rpm...

One other thing... even after getting a master caution and the boost falling down to .2 bar, I was able to get higher boost after I let of the gas and accelerate again.. It's like, I almost do feel that the DME sees the boost, senses detonation and retards the timing, then i shift and it happens again... it never actually LOCKS me down to .2 bar of boost.

Dal Heger

Yup, so find the cause.

The master caution isn't hooked up to the DME. Forget about it. You have a lose wire somewhere behind the dash.

When have the fuel injectors been serviced last?
It could be that one is partially blocked/has a bad spray pattern. It's cheap and easy to take them out, take them to a place that cleans them using the ASNU system and replace them. ~$100 or so.

You might also check the fuel pressure. Make sure that is within spec. Maybe replace the stock fuel pressure regulator (back of the fuel rail) with an adjustable rising rate one.

You did check the electrical plug to the CV right? Make sure it's nice and clean/tight.

porshhhh951

boost cut. or detionation. Although when I was in your car the other day I didnt hear any detionation what-so-ever. Lets take the car to perrys to have the full inspection done and we will know everything then. He is the best.

We knew it wasent your wastegate because you said sometimes you could read full boost and sometimes you couldnt. The first obvisou thing would be to clean your injectors,check your coil and your plugs,change the fluids and see how she runs.

Also are you using 93 octane at the pump or something less like 87-89? Cause its my expeirence our cars run like **** on crap gas.

Danny call me like around 11 or 12 tomorrow and let me know what you want to do. Cause Jake is prolly going to be meeting up with us.

Dal Heger

You won't hear knock. If the system is working properly then the DME will retard the timing/cut boost to control the knock before it becomes perceptible to human ears. That's the way it works. If you hear knock, then it's more than the system can handle, or it's a rod bearing!

Dal.

danny951

I use 93 octane every time. And I'm still on for taking the car to Perry's and dropping it off for him to comb over. It very well may be my injectors and I'm wondering if it would be a good idea to go ahead and put in larger injectors, or if that would screw up performance since my chips wouldn't account for them. Anyway, I have all the records of the previous owners so I'll bring them along.

I'll try and talk Brian into sticking around and eating with us. We're still on though for around 5ish today.

danny951

ah, well according to the guru site, my guru chips have a switch to allow for larger injectors..

"These chips have also been programmed with your future upgrades in mind. You can pick fuel-settings for stock 34.5lb/hr stock injectors as well as 55lb/hr, 65lb/hr and 75lb/hr aftermarket injectors with just the flip of a switch! You won't need to make any fuel-map corrections or fuel-pressure adjustments to use those injectors later (we recommend a fuel-pump upgrade with 75lb/hr injectors)"

So maybe I'll go with some 55 or 65lb/hr injectors if mine need replacing.

Dal Heger

There is no reason to NEED to put in larger injectors, unless you are going with a bigger turbo and more boost.

Get the injectors serviced. They will come back better than new. Check you ASNU's site for the information. I've had that done on both of my cars, they give you a before and after reading. You can feel the difference, and it's relatively cheap to do. Hell, I'd even put new from the factory injectors through the process to make sure they match up (most don't).

Dal.

NZ951

If they need replacing, get some 55 or 65 depending on you HP goals. Racetronix have sets of 4 for around USD200. Its a no brainer really.

danny951

gotta love rennlist, two responses... two totally different opinions.

No really, thank you both for the feedback. I will probably just service the ones I have if that can be done, but if I end up HAVING to replace, I'll get bigger.

Dal Heger

Well if you HAVE to replace, there's no reason not to get an improved (bigger) version.

My only point is that unless the coil in the injector is bad, you won't have to replace them. Fuel injectors are really, really, really simple and robust little valves.

Dal.

NZ951

I agree the injectors will likely be fine. Remember they max out at around 280-290. As long as your goals will always be to ave less power than that, you will be fine with stock.

Luis de Prat

So, this test would indicate that the cycling valve is at fault and you should get full boost again by replacing it?

I'm having a similar situation in a stock setup and don't want to bypass the CV. Should I just replace it?