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-   -   swapped in a used jdm engine. idles fine then dies (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/swapped-used-jdm-engine-idles-fine-then-dies-1110764/)

Naps 02-18-17 09:50 AM

swapped in a used jdm engine. idles fine then dies
 
I picked up what looks to be a rebuilt S5 TII jdm engine. It starts good idles great for about 6 seconds then boggs down and either dies or misfires and idles fine again. In order to start it at all the CAS has to be all the way advanced (clockwise). I even restabbed it and used my spare CAS. I turned the idle screw up and it does the same thing dies after 6 seconds even when i hold it a 3k it will drop in rpm.. When i got the engine the plugs that were in it were ngk platinums heat range 6:scratch: and the CAS was originally set all the way clockwise.

Im running a haltech ps1000. my other engine ran fine before a seal let go.

I wounder where i should start. could this be a problem with timing? Is the problem specific to this engine?

The engine bolts were all numbered and the oil pan look like it had clearish gasket maker that why im guessing it was rebuild. I have not done a compression test because it starts up on its own and will hold a good momentary idle

Naps 02-18-17 10:07 AM

heres a video of what its doing

https://www.youtube.com/watch?v=-rlwG7Cb1tM&feature=youtu.be

RotaryEvolution 02-18-17 11:11 AM

sounds like it is doing the idle bounce, but can't catch it and return to idle. probably due to many various reasons. basically your idle is too high, but why? is the question.

vacuum leaks causing a lean condition likely why it can't catch and dies. fixing the vacuum leaks would likely cure most if not all of it.

embedded 02-18-17 06:26 PM

https://cimg4.ibsrv.net/gimg/www.rx7...7ead0b54ad.png

When I set the timing lock to 25* BTDC. The yellow notch on the crank pulley lines up with the timing pin on the engine with a timing light.

This is with the front rotor 1 leading plug hooked to the timing light.

Are these pins supposed to line up at 5* ATDC? meaning I am 30* off in timing?

also there was a small vac leak that we fixed. it was only pulling -4psi at idle now its at -8.5 psi

RotaryEvolution 02-18-17 08:15 PM

are you the same person? 9" vacuum is still really low...

embedded 02-18-17 08:21 PM

I'm his brother. His Haltech is set up in psi, so -8.5 psi or about 17"HG. Sorry about that.

RotaryEvolution 02-18-17 08:26 PM

well, then your map is probably lean, perhaps it was tuned to a worn out beat to snot engine and now needs more fuel to idle properly.

embedded 02-18-17 09:04 PM

After messing with the timing, I trimmed the fuel a bit and got it to idle smoothly. So now our goal is to try and get the Haltech timing to match the engine timing.

embedded 02-18-17 09:15 PM

This is how the trigger is setup
https://cimg2.ibsrv.net/gimg/www.rx7...c8284fca96.png

RotaryEvolution 02-18-17 09:59 PM

base timing lock in the haltech should be -5 and 15 split, iirc. then the right pointer should line up with the leading #1 and left with trailing #1

Naps 02-19-17 07:28 PM

Thanks for the help rotaryevo :icon_tup:

https://www.youtube.com/watch?v=AYRa...ature=youtu.be

thats what its doing now. my brother says its my tune thats messed up... where should i go about finding a base tune for haltech ps1000, 1000cc injectors w/ a garrett t04

https://cimg4.ibsrv.net/gimg/www.rx7...430d9ea356.jpg

RotaryEvolution 02-19-17 08:05 PM

sounds like your CAS offset is a bit off, could be the CAS is stabbed improperly. if you offset too much then the haltech will sound like it's running on one rotor at times.

there is some maps on the haltech site, but mostly for stock applications. save your original map before trying another and do not boost much with any other maps, since you are running a much larger turbo that will need to be tuned specifically for your car.

Naps 02-19-17 08:10 PM

We used a timing light and got it dialed in though. Ive stabbed it multiple times with another cas and got the same results... i can try it again. looks like who ever had the engine before me in japan painted fresh yellow on the mark and the red is barely noticeable maybe my brother can chime in and explain better

RotaryEvolution 02-19-17 08:15 PM

well, typical trigger angle in the haltech will be about 65-67ish degrees, if it is much further off than that then you may have issues within the haltech with the timing.

are you using the trigger angle or adjusting the CAS to get base timing set?

scroll down about 1/4 of the PDF for crank sensor stabbing, offset and angle base setting for rotary, base timing lock degrees, etc. not the same ECU but the instructions will be the same for timing.
http://www.pacperformance.com.au/Art...se_website.pdf


i noticed your angle is over 70, which could be the issue if you are using angle to set the base timing. your tooth offset is also 11 instead of 10, which means the CAS is probably stabbed incorrectly so the haltech can't compensate for the large gap in the CAS timing and actual engine timing.

embedded 02-19-17 08:27 PM

So we got the timing dialed in with a tooth offset of 11. Then I traded a tooth for some trigger angle and dialed in the timing. with these specs. It ran the same both ways.

We will try adding some fuel to the map tomorrow and see if it just a lean issue. I can get it to idle well. Also, as long as I keep blipping the throttle it revs well and AFRs look good. As soon as I stay in one place too long it seems like transient enrichment decays away and the engine leans out.

https://cimg6.ibsrv.net/gimg/www.rx7...ddcdc7813a.png

RotaryEvolution 02-19-17 08:32 PM

still sounds like the CAS is a tooth off with the angle being so far out of whack from where it should be.

could also be a lean idle map according to your description but the way it sounds doesn't really sound like a simple lean issue to me.

Naps 02-20-17 04:25 PM


That's what it's doing now after setting the cas multiple times in different spots near the mark... the video is the another cas set exactly on the right tooth. it does the same thing everytime.

I hooked jumper cables from my engine to the ground on my car and it does the samething.

I'm thinking there's a possibility the haltech is bad?

Naps 02-20-17 04:33 PM

The engine that blew before this only had 2500 miles on it. it was an s5 tii with new fd hrdened mazda oem seals. my tuner thought my gas tank was empty but it was full. He thought it was a fuel issue. now I'm kind of thinking the haltech went bad and blew the engine.

Naps 02-20-17 08:20 PM

ran into more problems. that turbo cartridge was brand new :(https://cimg0.ibsrv.net/gimg/www.rx7...22182c25f.jpeghttps://cimg1.ibsrv.net/gimg/www.rx7...faac5aeb0.jpeg

RotaryEvolution 02-20-17 08:26 PM

must be a 35R, unfortunately their ceramic bearings are far too touchy.

Naps 02-20-17 08:43 PM

https://www.horsepowerfreaks.com/gar...150902843.html

its this one. that went into this turbo

https://www.vividracing.com/catalog/garrett-turbocharger-60-tb4137-p-150903359.html

all i did was idle and small revs i never went anywhere

Naps 02-21-17 07:41 PM

https://cimg1.ibsrv.net/gimg/www.rx7...5c8beedb6.jpeghttps://cimg3.ibsrv.net/gimg/www.rx7...c051390a4.jpeg

Naps 02-21-17 07:44 PM

so i swapped that little oil seal from the turbo that got chewed up from my previos engine into my new turbo and that fixed the problem! no more oil gushing into my downpipe. i wounder if someone could explain that one lol

also my compression is about the same on all side of each rotor so my engine is in great shape... it just goes into lean episodes.. this wekend im meeting up with my tuner and hopefully he can figure this out..

RotaryEvolution 02-21-17 08:44 PM

obviously it wasn't a real Garrett rebuild, but for that price you could have had a brand spanking new 35R...

embedded 02-21-17 10:14 PM

Here are a few vids of the engine:





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