Hello all.
I need some serious help here. Last October, had coolant in my oil. Cracked block on my LNF. Did an LDK swap with new Opels. Had problems from the get-go with getting it to run. Eventually, unplugged the MAF and got it to run fine - just with the CEL on. I changed the injector constant for the Opels and kept my tune the same otherwise. Car ran great and trims were +/- 3%. But if you plugged the MAF in, it would stall out. If you tried to start it with the MAF plugged in, it would start and stall in about 5 seconds.

Thought huge boost leak. Okay no big deal, I don’t drive it in the winter anyways. So I tested for leaks, sure enough, big leak in the intercooler. Put a new intercooler in this weekend. Started the car. Plugged the MAF in. Ran great. Drove it around all day. No problems. Got home, cleared the stored code for the MAF being unplugged. Started the car and it did the same thing as before - died after 5 seconds.

Only other relative info/change after the LDK swap would be a purge tank delete (the one under the Intake Manifold) and that is 100% plumbed correctly.

I am truly at a loss and if anyone has any bright ideas I would really appreciate it.

Pic of engine bay for fun.

 

What does your maf freq look like when you start the car and it dies?

If you have hptuners set the base MAF table to all 1.0 and see if the helps the car run longer. The VE of an LDK is different than the LNF, so that area could likely use a tune adjustment.

I'm also assuming you put the clamp back on your upper charge pipe (missing the picture)

Side note even if the vacuum tank delete is routed incorrectly the car will run just fine in vacuum, just boost control is wonky.

 

ECaulk,

Thank you very much for the response. Yes the clamp was put back on! Haha.

I will set that table to 1.0 and report back. I will try and take a log as well.

 

Update: I changed the MAF base table all to 1.00 across the board. Started the car. It ran like garbage and died. So basically no change. Unplugged the MAF and it ran perfect. Put about 75 miles on today with the MAF unplugged and it runs great. I attached my tune and a log with the MAF unplugged. Around 11 minutes, I plug the MAF in and you can see the behavior. ECaulk, would you be able to take a look and give an opinion??

Full disclosure, when I swapped in the LDK (back in October; didn't touch the car after that til last week due to winter/salt) and was near finished I hooked up a ground* near the starter. This ground was actually hot. Took a second to realize what I did. I am wondering if perhaps my ECM is fried. I would just assume there would be a host of other electrical issues but literally the only issue is the car not being able to run with the MAF plugged in. I ohmed out between the MAF and the ECM and there is continuity in all 5 wires. I have swapped MAFs with a known good MAF. I am seriously leaning towards the ECM being wrecked. Is there a way to determine if that is in fact what's wrong except just buying one from ZZP and trying it?

 

I should have some time this weekend to give your log a quick check, that is assuming I don't have to many honey-do's.

Have you checked the voltage supply for the maf? If the voltage being supplied is incorrect it could cause all kinds of issues. I've never really looked at this car from an electrical system physical interconnection to say if the hot connection near the starter instead of ground would cause any issues.

 

Thanks for helping people Eric!

 

I have checked for voltage at the MAF and there is voltage.

 

I would start going over all your wiring, you have strange accelerator pedal response after you plug the maf in, unless you were playing with the pedal like a honda off redline something is up in that range.

Sadly this means pull the wire loom apart, you need to chase the wires all the way back to the ecu, you might be able to shorten your effort by looking for any worn areas in the loom and starting there.

Another option is to pull a 100% stock tune, adjust the injector constant and then log. I haven't checked the injector constant you have input in your file vs the value I use as a starting point (tuning computer is charging currently).

 

I was playing with the throttle when the MAF was plugged in. I tried to do that in order to keep the car running. I have tried the 100% stock tune with the updated injector constant and it does the same thing unfortunately.

 

Then I would start checking all wiring physically for damage not just continuity, checking sensors for the correct resistance and supply voltage.

 

Today, I physically checked voltage on the MAF harness. Two 5V references and 12V supply were present. Checked for boost leaks again, small boost leak on the intake manifold. Ordered a new gasket and will hopefully be able to install it this weekend. I'm not holding my breath that this will solve my issue. Being that I had no issues whatsoever prior to the LDK swap, I am truly baffled...