Ok so I have gotten the new motor in my s70 and it starts and idles great. I think I killed the starter because when I turn the key all I hear is clicking and the car wont jump start. Just need a confirmation on that but thats minor. Thought I had a boost leak but I am really not sure. Hooked up the boost gauge and im reading a lot of vacuum at idle. But when I accelerate it immediately hits zero and wont build from there. I have tried to disconnect the wastegate and make sure its sealing, still nothing. Bypassed the TCV to eliminate that possibility, and cant find anything in the intercooler hoses. It threw a MAF code so I suspect its going in to limp mode from a bad MAF and not allowing itself to build boost, but I dont know what limp mode is since I havent had this car run to its fullest since I bought it. So here are my questions:

1. Could all this be caused by a bad MAF? and how do I test it?
2. The turbo seals are not blown and the thing is spinning, so what else could cause a lack of boost with the wastegate not attached?
3. Does good vacuum eliminate the possibility of leaky turbo lines?
4. If it isnt the MAF, what else could it be?

I will more than likely buy a new MAF but If this doesn't solve my issue I will be pretty damn stumped. I refuse to give up on this car and since it runs, revs, and shifts good I feel like Im 90% of the way to getting this to be a good DD.

 

Regarding the starter, after you check to make sure your battery cables are clean and tight, if it still is clicking, I'd disconnect the serpentine bent and turn the engine over by hand. I had the A/C clutch fail and it prevented the engine from turning over.

 

Also, as a general rule, its a good idea to fix the simple stuff first. Sometimes the simple things make complex systems fail. Example, you are asking if the MAF could be creating a boost issue. If I were asking that question I'd clean the MAF and make sure that is good. The car should run and perform reasonably, at very low RPM, even if the turbo were seized.




If the turbo is spinning (you said it was) and the seals are good and you close the waste gate you get boost. External stuff act as a control mechanism but will not prevent the boost if you bypass.

 

It is running well at low rpms but beyond a certain point its feels like its holding back. With all that bypassed should I do more examining of my wastegate?

 

Could your wastegate be slow or binding. maybe stuck partially open? Did you check to see if the diaphragm is functioning correctly? Is it completely closed under vacuum or maybe stuck partially open. You'll need a manual vacuum pump for that. You might also make sure the diaphragm is holding vacuum.

 

I'll check on the wastegate but ive had 3 different turbos on this car and it has never boosted. So that leads me to believe the problem is something that has been consistent among the 2 motors and 3 turbos ive had in this thing. I cleaned my MAF and replaced the starter(tested so I knew it was bad) and I found out my couple month old battery is only putting out 3 volts......I just cant win lol

 

You're probably going to find out the alternator is bad. Have the parts place run a load test on the battery. If nothing else, it gives it a charge. Takes them about 1 hr to run the test.


Regarding the turbo, its really a pretty easy piece of gear. Hot exhaust has enters, the wastegate diverts to control speed. The pump is driven by the exhaust turbine. Air goes to the intercooler. Air goes to the engine.


If you have had 2 engines and 2 turbos, you are either very unlucky or you need to look upstream or downstream of the turbo.


Upstream would be the air filter since that can restrict the volume of air. You can't compress air if you can't get the volume. make sure the air intake is clear and the filter is good.


Downstream would be the feed tube to the intercooler, the intercooler and the feed tube to the engine. check out the whole path and any components attached to it like a metering valve or something. I recall there being a valve in the back from RSPI's PCV replacement video.

 

Well its fine now. Once I had the starter ran at NAPA and installed it again its shown no problems. I'll look for any leaks because it seems to get to 0 instantly and create vacuum as I go down the road. Either that or the gauge is slightly off but it still gives me some visual reference for what the boost is doing. I can definitely hear it spinning when it should so yeah, check for leaks, replace air filter and go from there