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LH2.4 swap, Speedometer

Starter gets cranking signal thru the blue yellow wire on the small pigtail on the existing firewall harness. (see pic of this pigtail above. Plant pic.)

We had red/blk and solid blue backwards. Red/blk was ign power and blue was speedo. Not the other way around as previously mentioned.

Oh, and the 4th wire was just extending a blue wire by the coil and hooking it to coil for 12v switched with ign on.
 
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So it fires up every time effortlessly. The only issue so far is a lot of idle surge. Goes consistently up and down to around 1500rpms. Gonna recheck for airleaks and tps values at ecu. It clicks when opening or closing the throttle though. Any ideas?? I did a search and TPS, airleaks, and IAC are suggestions. I also know 2.4 acts up with different injectors. Right now we have orangetops and no resistor pack.

Edit- and no codes. 1-1-1 on both fuel and ign test sockets.
 
ZVOLV, this is exactly what mine is doing. When I unplugged my MAF, the car idles perfect. Let me know if you figure anything out. I will do the same.
 
We will recheck the MAF relocation wiring. The MAF is an almost new looking one we snagged from a very clean dealer serviced 940. There is a very new Volvo part number sticker on the thing.

What injectors are you running? I know my 940 had idle surging probs once after changing to browntops.
 
We pinned out the MAF, TPS, and temp sensor leads and they all check out. It also passed the mode 2 and mode 3 diagnostic tests. Changing IAC didn't help either.
 
Here is a goofy viedo of the surging idle:

http://www.youtube.com/watch?v=V8HCfLTIBKs

Do you think the speedo wire disconnected would really cause this? Or is it something else? All the sensors to the computers including MAF, TPS, and Temp sensor have good connections. TPS and Temp give proper readings. Havent checked MAF values at the computer yet. I think its 2.4 not knowing what to do with 850 Turbo injectors. I know my car did some whacky idling with different injectors than stock.
 
With the MAF unplugged it idles like crap and barely runs.

It also passes the Mode 2 OBD test where you test the TPS, RPM sensor and one other component. It flashes a code that each one it OK.

It also passed the Mode 3 OBD test where it clicks the injectors, clicks the IAC, and then clicks the cold start injector.
 
ZVOLV, i have the wire for the speed signal hooked up to the gauge cluster and It still idles strange. If that wire is not hooked up and the car doesnt move, it theoretically shouldnt make it idle strange
 
Which wire is the wire we cut on the TPS that tells the computers to do a 100% duty cycle at WOT?

Also, could the o2 sensor be the cause of a constantly-fluctuating idle once the car is warmed up?
 
If you are making your car a turbo car and you are using the NA 240 harness you have to cut the wire that runs to the TPS that is the WOT wire as turbo ECU's don't use that and if you leave it hooked up it will cause your injectors to fire at 100 percent with certain ECU's when you floor it. Also if using turbo low impedance injectors you have to add the resistor pack. Also when you turn the key on the fuel pump relay should click on and the pump should run for a few seconds if it's hooked up right. 2.2 doesn't do that.

Dear sbabbs

My 1993-240NA2.0 swap to B230FT. When I ignit on,the injector getting very hot.

Should I cut the wire which runs to the TPS??

I check the harness to LH2.4(IGN ON),
pin2:TPS-signal-input(white-yellow::0v).
pin3:TPS-signal-secound-input(white-blue::12v).

Should I cut these 2 wire??

thanks.
 
Dear sbabbs

My 1993-240NA2.0 swap to B230FT. When I ignit on,the injector getting very hot.

Should I cut the wire which runs to the TPS??

I check the harness to LH2.4(IGN ON),
pin2:TPS-signal-input(white-yellow::0v).
pin3:TPS-signal-secound-input(white-blue::12v).

Should I cut these 2 wire??

thanks.


The wire from the TPS doesnt relate to the hot injectors. Do you have turbo injectors fitted? with or without the ballast resistors?
The non turbo 240 injectors are high impedance and work without ballast resistors fitted
The turbo injectors are low impedance and need ballast resistors to limit current.

If you use turbo injectors without the ballast resistors you can damage the LH-jetronic box. The injector driver transistor gets damaged and makes the injectors stay open all the time because it closes the circuit when broken. The fix is pretty easy if you are handy with a soldering iron.

About the TPS, only cut the wire that gives the signal for full throttle. Not both.
 
Yes cut the one wire for WOT only, leave the other two as they are needed for telling the ECU when the TPS is closed.

I'll head out to the shop and take a picture of which one to cut in a sec...
MVC-037S-1.jpg

Cut the lower one in the pic with the red tester on it. This pic is a pic of the intake manifold upside down, so in your car cut the upper most TPS connector. This means the one closest to the hood.

Don't cut the middle one, that's the power. Don't cut the lower one, that's the one for TPS closed, you need that one. Video to come...

MVC-036S-1.jpg

Looking at it from the side at this angle, cut the one there on the left. It's labeled 3 on the black plastic there. The middle is labeled 18 and the one on the right labeled 2.
<iframe width="420" height="315" src="http://www.youtube.com/embed/0cbr--8QJio" frameborder="0" allowfullscreen></iframe>
Simon
 
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The wire from the TPS doesnt relate to the hot injectors. Do you have turbo injectors fitted? with or without the ballast resistors?
The non turbo 240 injectors are high impedance and work without ballast resistors fitted
The turbo injectors are low impedance and need ballast resistors to limit current.

If you use turbo injectors without the ballast resistors you can damage the LH-jetronic box. The injector driver transistor gets damaged and makes the injectors stay open all the time because it closes the circuit when broken. The fix is pretty easy if you are handy with a soldering iron.

About the TPS, only cut the wire that gives the signal for full throttle. Not both.

I swap whole B230FT into my 240(include turbo injectors). when I turn the key to IGN On.

It can't start. and the injector getting hot(the injector stay open all the time).

And then, I exchange the LH-jetronic box to the original 2.0NA-box.

But the injectors still stay open all the time and hot.:-(
 
We'll I know for a fact if you hook up a lh 2.0 ECU jetronic box to a lh 2.2 or 2.4 car you will fry the ECU. I did this just last week...

The LH 2.0 has different wiring for the AMM and it will smoke it because of this. You can repin your AMM wiring and use a LH 2.2 AMM with 2.0 but you have to change the wires first or you'll smoke your ECU..

As far as why your injectors are staying open and not working properly, I'd check your wiring. Did you change out to the B230ft wiring harness? Was it a 740 harness? Best thing to use is a 240 Non turbo lh2.4 harness for this type of swap...

Simon
 
We'll I know for a fact if you hook up a lh 2.0 ECU jetronic box to a lh 2.2 or 2.4 car you will fry the ECU. I did this just last week...

The LH 2.0 has different wiring for the AMM and it will smoke it because of this. You can repin your AMM wiring and use a LH 2.2 AMM with 2.0 but you have to change the wires first or you'll smoke your ECU..

As far as why your injectors are staying open and not working properly, I'd check your wiring. Did you change out to the B230ft wiring harness? Was it a 740 harness? Best thing to use is a 240 Non turbo lh2.4 harness for this type of swap...

Simon

I'm sorry for the words "2.0NA-box".

My car is 1993-240GL-2.0L-NA.

Does this car equip with LH 2.4 system?
 
I swap whole B230FT into my 240(include turbo injectors). when I turn the key to IGN On.

It can't start. and the injector getting hot(the injector stay open all the time).

And then, I exchange the LH-jetronic box to the original 2.0NA-box.

But the injectors still stay open all the time and hot.:-(

I guess that you have fried your ECU injector driver transistor. Replace with TIP-122.
 
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