D7ig

Hi,

i've swapped a S5 NA engine into my S4 NA including full wiring harness and all accessories.
I've done the TB mod with removed cold start assist and removed the rats nest. So there is much room for errors.
The MOP lines are removed, too, but the MOP itself is on it's stock location and is connected.

The engine starts quite good but doesn't idle. With slight throttle the engine is running more or less good. When driving the engine feels okay. If i push the pedal to the metal the first time at 2000 rpm after some warm up, it push's good. After 2-3 seconds it feels like it doesn't ignite the fuel. Then i can push the throttle only to 1/4, after that there are those hesitation problems again. Then the problem is not rpm related. So for one drive i can only push the pedal for 2-3 seconds to the floor. ;-)

What i've done allready to solve the problem:
New groundings:
- chassis to neg. batterie
- sec. fuel rail to chassis
- ecu case to chassis
- front iron to chassis

I've tried to set the tps, but there is a point where both test pins switches from 0 to 12v simultaneously.

The check engine lamp does not illuminate at all. Neither at key to ignition nor with the running engine. I looked the bulp, it "looks" okay. Is there another possibility to check the error codes?

Would be nice if someone could give me some hints where i could start the search.

Thank you,
Daniel

Rx7TyreBurna

iTrader: (1)

I didn't do quite the same, but I put the S5 UIM and IIM on my S4 LIM. Also did TB mod and emissions removal.

Previously, before I did the swap, my car would do what yours was. It was the LIM gasket that had gotten coolant on it and been destroyed. The coolant leaked from the nipple on the back of the water pump? The coolant nipple that was near the alternator.

Also, when I first started my swap, it kept dying. It ended up being caused my a leak in my VDI. The spot where the VDI valve is bolted on was leaking.

Sounds to me like you have a vacuum leak probably a big one. Try having a friend hold the RPM at 1k and then spraying starter fluid around and see if the car idles up. If it does, start looking for leaks in that area.

I also suggest using some ultra black RTV on both sides of your gaskets. Then make sure they are torqued to spec.

Good luck!

D7ig

Hi,

thank you for your suggestions. I heaven't checked for vak leaks yet.

But i was at the car and i've read the error codes now directly from the ecu connector with a resistance meter. That worked!
Don't know why the check engine light does not illuminate, cause the bulp itself is okay... I will check this later.

I got some error codes, many about missing solenoids and the 27 about the MOP. Hehe, okay, the car will go into limp mode, i think.

Thx, i bought some stuff like that this morning. I will check for vak leaks this weekend and i will get an other MOP next week.

Bye,
Daniel

D7ig

Ah. Great great great!

I put on the new / used MOP. Now the engine pulls very strong at WOT and so on. Yesss

Daniel