Timing or other issue after L67 to L32 swap

[67goat]

So I recently swapped an L32 into my '01 SSEi. Since I'm a weekend warrior, not FT mechanic, my brother's repair shop did most of the work. We got the car running 2 weeks ago and car runs smooth at idle and light acceleration. At higher loads though, the engine seems to partially cut out (as if either ignition or fuel delivery is being shut off). Its even more pronounced in 2nd or 3rd gear then 1st. Only had a check engine light once for about 2 seconds. When we scanned for trouble codes, found none. Ignition coils, wires, etc. seem fine. So inititally was left scratching my head with what it could be. Then a couple days ago, actually heard a bit of valve rattle, so right away, I'm thinking timing issue.

The balancer seems in good shape, so I'm wondering one of two things 1) could somehow the crank sensor could be sending erroneous information (maybe the sensor was damaged during transportation and/or install) yet not throw out error code? 2) Issue with knock sensor - but even if knock sensor is the issue for advancing timing too much, what would be cause of hesitation? Would the knock sensor shut down ignition or just reduce timing in any knock situation...though it definitely is not preventing over-timing when I'm getting valve rattle. Anybody have an issue similar to this before?

Lastly, I read elsewhere possibly the PCM from the L67 needs to be changed to be compatible with the L32, but that is not convincing since nearly all the electrical components are L67, the only L32 part is the engine itself which is all mechanical. The fuel rails, injectors, ignition module, TB (used the zzp adaptor plate on the 5th gen SC in order to re-use my TB), etc. are all L67 parts.

So wondering if knock sensors and/or crank sensors go bad without error codes? Anyone have any ideas?

[BillBoost37]

L32 is basically an L67. Check the knock sensors. IIRC there's something different between the two. Not positive. I've transplanted a ton of these and never had an issue. Check maf etc. maybe vacuum leaks.

[Rico]

Is the MAP sensor on the GEN V a 2 bar sensor?

What size pulley is on your GEN V?

You're using a GEN V with a L67 tune? You say you can hear the valves pinging.

Sounds like detonation due to:
A LA Bill - Vacuum leak or bad/wrong sensor - lean condition
MAF tuning is way off. Was the L67 tune previously modified?
You're using 33# injectors?

KR mostly causes the engine to lose power, not hesitation, unless engine is detonating.
Ideally, the PCM should be optimized for your particular setup.
Knock sensor DTC's = P0325 through P0334

[BillBoost37]

Map sensors are two different connectors. Likely he kept his L67 sensors.

I'm running a Gen V off an L67 tune. It's not that far off in actuallity because both blowers displace 90 cubic inches of air per revolution. Hence the M90 designation Gen V handing off a cooler charge.

Injectors..he's likely running his stockers. Since he can't swap the L32 rail on. but if not..great idea.

I'm thinking lean/vacuum based on the fact that it idles nice and light acceleration works well. Anything beyond that and as long as you aren't in boost.. ...hmmm now to rethink this. Do me a favor..triple check your plug wires. Make sure you have them right. Because it's possible to cross a couple and have it run nice and then go to hell at load etc. I know usually it idles like crap..but there are a couple cylinders you can do and have it be off. Trust me. lol

[Rico]

Injectors..he's likely running his stockers. Since he can't swap the L32 rail on. but if not..great idea.

This is what I'm doing. Rewire connectors and solder the pressure regulator and return line in there and you're done. I know it's unnecessary but it'll be different.

I'm sticking with your first inclination...lean and mean.

[67goat]

Yes, running stock injectors and L67 sensors. The L67 PCM was enhanced by Intense for the mods originally done to the L67 (3.4 pulley, 1.95 rockers, fwi, colder plugs, 180 stat). I now moved down a step to a 3.5 pulley in the L32 and added headers. I was thinking same thing with the lean issue initially until I later heard the valve rattle. I even had one brief run-on situation on a warm day (lasted about one second when I turned ignition off, but recognized what happened instantly), which takes me back to the timing issue - seems even at idle with stock injectors engine should not run-on unless timing is either too high, fuel quality is poor or engine overheating. Temp was 185-190 at the time on a 75 degree day, so nothing atrocious and running 93 octane fuel. We're going to start by re-torquing the knock sensor - if no luck, replace with new one. Will also double check the wires. etc. If no luck, will come back on here. Not sure what you mean about soldering the regulator/return line - do you mean eliminate the return line? I'm not sure about that unless I run a corresponding pump/regulator built for no return line (that's how the L32 is right?). I was thinking about eventually replacing the 90k mile factory fuel pump with a newer one, but not sure what best brand/quality/type should be yet (mine seems fine now, was planning to replace just as insurance).

[BillBoost37]

Goat.. Rico was joking with me. Sorry.

Test fuel pressure
Please snap a picture of the engine bay/motor. I know you are meticulous from prior posts/talks. Just wanna see what the guy did. You know..to peek at it.

[Rico]

Oops, sorry about joking around.

You have a real Frankenstein's monster there.
What happened to the L67? ?

If you can't find anything with fuel pressure or something obvious in the bay, a stock tune and a stock pulley may be a good starting point.

So you transplanted the knock sensors from the L67 to the L32?

[BillBoost37]

Not yet...lol c'mon give the guy a minute. He just learned they are 14ft lbs for torque.
Oh..another thought..if he pulled them or checked them ...maybe he overtightened them.

I have a few ideas...but ya know. can't give away all the info before it actually materializes in my brain.

[Rico]

Not yet...lol c'mon give the guy a minute. He just learned they are 14ft lbs for torque.
Oh..another thought..if he pulled them or checked them ...maybe he overtightened them.

I have a few ideas...but ya know. can't give away all the info before it actually materializes in my brain.

See, I'm actually applying what I've learned from you and the others on this forum. Hence, the question.

[BillBoost37]

I see what you're doin.. I do. Just like I realized you were joking with me and when he didn't ....I splained it.

so Chuck..you got a schematic for this issue?

[Rico]

Oh...I got a schematic. If your not bein' funny - I give you one.?.?

[67goat]

So since I have a day office job - gave car to my dad to take to shop. Wires were checked and were fine, re-tourqued the knock sensors yesterday. I got car back last night - went for quick test drive. In 1st gear car did not break up, hesitate, etc. Gradual acceleration pressure seemed fine, so did one test to wind through 1st gear and car ran like a champ (temporary cautious optimism). Tried again where I can get into 2nd gear, this time in 2nd gear, same symptoms of engine shut down. Got a flashing SES light for 20 seconds, then computer resets and is gone. (no scanner at home to see what code is)
Pulled back into garage at home, checked for any obvious signs for source of vacuum leak. Double checked the throttle body adaptor bolts. 2 were not overerly snug and I was able to torque down another 1/16 of a turn. Take car back out for test ride. Almost same results, this time at top of 1st gear, SES comes on and stays on. So done driving and back to the shop for scan.
Before a parked for the evening, I tried one test by just coasting at about 25-30 mph, then manually downshifting to 2nd and then tried to accelerate - experienced cycling hesitations almost immediately. Very odd it would not do that in 1st.


To answer Ricos question - the L67 suffered a spun bearing at 91k miles. The bearing was paper thin so must have been a long time issue. Part of the reason I switched to the L32 was hoping the factory rods and bearings would fare better.

So back to the drawing board - will plan to scan, check fuel pressure, etc. Will try to post engine bay picture some time in the next day or so. There was one extra vacuum port on the Gen 5 SC that did not exist on the Gen 3, so we just plugged it - not sure what it ran to in the L32 engine bay. Because this an inconsistent issue and a used jy engine, I'm betting something may have been damaged either in the yard or during transport (we used the L67 knock sensor because the L32s were damaged), so I'm thinking something else is sending incorrect or conflicting information to the ECM.

[BillBoost37]

There was one extra vacuum port on the Gen 5 SC that did not exist on the Gen 3, so we just plugged it -

Bingo... get us a picture or verify what it is in the pictures I'm about to post

[Scottydoggs]

im just gonna throw this out there and see if it sticks......hows the cat? could be clogged.

[BillBoost37]

Is it the one with the hose attached or the one just to the left of it?

Hose is pcv. This must be hooked up or you are possibly building pressure in the crankcase...which..btw would cause it to fall on it's face. PCV gets routed between map and throttle plate.

If you have an L67 TB and want to make the pcv functional, follow the first 4-5 pics in the first post of this thread to drill and tap your L67 TB. Then run the hose from that pcv nipple to the new nipple you put in your TB. If you need more pics..holler. I have this on my car.

Other one is the L32 evap hole and needs to be plugged and or have the evap routed into it. It's easy to tap with a 1/4" npt and put a nipple in it to put the vacuum hose to it. I know..cause I did it last night.

[BillBoost37]

I'm doing my chair dance....cause I know we at least fixed something that isn't 100% right.

[67goat]

Ha! Will check Boosty! My brother did the install and he's a FT mechanic, I assumed he would've not plugged somthing as simple as a PCV. If that is it, he will never live this one down. Will let you all know the results...

[BillBoost37]

Don't give him a hard time.. you modified stuff w/o giving him the info about how it's supposed to be modded. It's not like a mechanic has a full diagram (like Chuck does) about what each port, orifice and wire goes to.

[BillBoost37]

Oh...also..make sure that evap hole isn't wide open. That would cause a lil problem too.

PS.. you didn't mention the plugged stuff in your first post. I see you are holding back info... did I ask for pics? hmmm probably would have seen that in pics....if the slacking OP had posted 'em.