Video: Bad idle, No power Problem

[g4ebguy90]

‪DSM MOVIE FOR DSMFORUM.wmv‬‏ - YouTube

 

[thomcasey]

Well, that isn't the ISC. Have you performed a boost leak test? Also, disconnect your MAF and see how it runs.

 

[g4ebguy90]

Ok, If i unplug the MAF the idle really doesn't change much. Sometimes it will get worse, sometimes it improves, usually doesn't help at all. What I did find out though, was that with the MAF unplugged I can floor it in 1st and it really goes. Unless it's full throttle it will miss and hiccup the whole time though.

I have not performed a complete boost leak test, I will soon, But I did go through all the pipes and re did connections.

I have had cars with boost leaks before, this is like a huge big time leak if there is one. But I swear I can't find anything. I doub't it's a air leak.

Seeing how performance is variable, I'm going to do a fuel filter and see if it improves at all.

 

[miguelmcv]

Give some more Info about the car or update your profile.

It has a N/T in it.

The Car in the Video is a Turbo.

Is this a N/T to Turbo Conversion?

If it is... What ECU are you using.

By the way.

Do a boost Leak test.
Check your timing.

GIVE US SOME MORE DETAILS.

 

[92AWDHX40]

Did you post this idle issue twice? No power vacuum leak, do a compression test. Worst case scenario take it to a mechanic.

 

[g4ebguy90]

Ok, I bought this car the way it it. I have owned it for only 2 WEEKS. I have already had to swap blocks. The head from the old engine is on the newly installed block you see before you.

The car is a 1991 GS, With a GST engine. The car ran just fine with the old motor, until it spun a bearing. So everything is there to actually run a turbo engine in this car.

I believe the ECU is a turbo ecu.



Timing for the belt is spot on from what I can see.
I am going to adjust with a timing light soon.

Because I can't tell if it's a sensor or anything I have been making many threads, relating to timing, ignition, ISC, etc etc. So it might seem as if I'm doing that.

 

[92AWDHX40]

Just noticed a turbo car, follow the steps for idle surge, boost leak test how long have you had the car.

 

[miguelmcv]

Make a boost leak test and see how it turns down.

If it is working better with the MAF unplug, then your MAF is OFF. But. Before you replace it, do a boost leak and check for timing and go from there.

 

[g4ebguy90]

I have done almost all the idle surge tests. For how long I have owned it, look at post above.

 

[miguelmcv]

Reading your posts, it looks like you best bet is, to Change your MAF.

That should fix the problem.

 

[92AWDHX40]

How to you tune it, any logger, dsmlink?

 

[miguelmcv]

How to you tune it, any logger, dsmlink?

I don't think he has something to tune it. it doesn't has anything in his profile about bigger injectors.

 

[g4ebguy90]

It's all stock bro. No need to tune. Its more then fast enough in stock form .

As far as the MAF, wouldn't it throw a code? I have no engine lights, the light does come on when it first starts though, then goes off like it should.

Could I use a non-turbo MAF? to check it out or???

But when I unplug it, it still acts up, and on the old engine it ran just fine when I pulled it.

 

[92AWDHX40]

Welcome to dsms.

 

[g4ebguy90]

Welcome to dsms.

, I know... I have had 4... in just like 1 year. Love hate relationship. Notice the 92 in the backround, sitting high with no engine in it .

 

[miguelmcv]

Some times it doesn't shows that is BAD.

When the MAF goes off. It can still starts, But when REV. It doesn't respond well, which the ECU is not receiving signals from the MAF and will get harder to give the right Fuel amount.

When is not on REV. It will keep running which the ECU assimilate the signal to keep it running.

When MAF is off. It will give a wrong signal to the ECU, which the car will not works good, so that's why, when you disconnect the MAF,,,,,, The ECU will assimilate the signal and will make the car to works better. (AGAIN). It will work better when not REV. the Engine.

 

[g4ebguy90]

So these cars can't make up for a disconnected MAF, I know newer cars can run without them installed. But maybe these old ones NEED IT. Ok, Like I said can I install a non-turbo to see if it helps?

 

[miguelmcv]

No. It wont work.

A turbo MAF has 7 pins.

Which a N/T has 6 pins.

I be leave the connector is smaller on the N/T.

Look at a Yank Yard, which they are cheaper and wear for a MAF to be OFF.

 

[g4ebguy90]

I thought the NOn-turbo MAF didn't have the extra pin because it's for the stock boost gauge?

 

[ExpresS]

I thought the NOn-turbo MAF didn't have the extra pin because it's for the stock boost gauge?

No the n/t plug is a different shape/size. Have you found the problem yet?

 

[g4ebguy90]

No i havn't.

Since this was up. I have swapped ECU's, MAFS, COIL, TRANSISTER.
I set ignition timing. Idle still is iffy and loss of power is there. Funny thing is, with the MAF unplugged it runs better, doesnt idle better, but it gets up and goes better. To top it off my turbo is making a little high pitch noise when it starts boosting. Hopefully its not taking a dump. That thing was hard to install on these.

Idk whats wrong with it.... I'm going to drop the tank and replace the fuel pump and see if that helps.

In that video nothing was swapped or checked. Since that video it has a diff ecu.

With the MAF plugged in and the ignition timing spot on, it idles around 700 now when warm. At cold start it still kinda does that 1000-1500 thing.

With the MAF unplugged idle goes from 700 to 1000 and does the idle surge 1000-1500.

Very weird.

 

[ross4g63spyder]

boost leak test

 

[g4ebguy90]

I have not done that, but re did piping multiple times. But I will give it a shot.

 

[ExpresS]

It's not a boost leak or a bad maf. My car is doing the EXACT same thing. I'm thinking it's a fuel issue. Try swapping the injectors. It's a DEAD miss at idle.

 

[g4ebguy90]

with the MAF unhooked she pulls. weird