Dead cyl issue

[T45]

This thing is killing me! I finally got a replacement injector in, thanks TMO! and fired it up. Still missing on cyl 2. I kill the cyl in consult and nothing. I checked the injector and it's clicking, I pulled the plug off the injector while listening with my trusty stethoscope (screwdriver) and it's working like it should.

So I then pulled the coil, ohmed it, checked + and - and both are good. I tried to check for a pulse from ecu and got something but it's really hard to make out on a digital multimeter. It matched cyl 4's pulse so I assume it's good. I took an ohm reading of the wires from the ecu to PTU and they all match so I am assuming that the wiring between the ecu and PTU is good. PTU ohmed good as well.

Checked compression and the comp is good, it is below spec but cyl's 2 and 4 matched so I assume between the overbore pistons and new, unseated rings that this is acceptable. Plugs are brand new and plug 2 comes out wet from fuel.

So, today I am going to swap the coils from cyl's 1 and 2 and see what happens. Then I'll swap the PTU's if the coil turns out good.

Anyone ever have a bad coil that ohmed good? PTU?

[redhat-z]

I hate to ask such a simple question but, are you sure its not the spark plug? I know they are brand new but it could be defective from the manufacturer. I have had this before. Plus, its a simple check.

[craigztoyz]

or plug could be fouled. noid lights help with the injector problemsolving.

If the coil swap doesnt help, then check compression on that cyl. Bad question, but oil is not milky, and water looks good too right?

[T45]

I already checked compression. I will swap plugs with 2 and 4 tomorrow and see what I get. I switched PTU's this morning and it didn't change anything. I don't feel like screwing with my intake to get the other coil off so I'm just going to order another one after I eliminate the plug.

I totally forgot I have a brand new set of noids in my toolbox. Duh. lol

I'll check plug and use noid and possibly swap coils, it will depend on how pissed off I am at that point.

[tmorgan4]

Glad to hear they arrived!

This stuff is frustrating isn't it. I was so jealous when I saw how easily the coil packs are accessed on LS1s and such. I hate taking out 4 bolts that are hard enough to get to just to get to the plugs.

Why not try taking off the #2 cylinder coil, hook up an old spark plug wire to one end, plug a spark plug into the other and see if it sparks on the chassis?

I remember reading a random post by Q45tech a while back talking about bad coils. It sounds like it's not a common issue but they do go bad occasionally. Not easy to diagnose a bad one either. Sounds like they normally just replace them and see if it helps from what I remember.

[T45]

It must be coil week at my house or something. Friday I finally got the engine back together for the car I bought for my mom. Its a Sebring Convertible with the 4G63. Don't ever buy one. Every other bolt is a different size, mm, std, and you have to take off 4 things for every one thing you want to get to. Most frustrating car in the world! And it eats anything you drop too!

Anyways, after getting it back together, no spark. I diagnosed for 2 days and the only thing I can come up with is the coil. Should read 12-15k ohms and is only reading 9k. I guess I'm about to throw an $80 coil in it and see if that fixes it. Stupid dsm engine has an auto-shutdown relay that took over a day to diagnose.

I am supposed to be enjoying this ****! lol

[T45]

Ah, another great day! Swapped plugs and nothing changed. Swapped coils and nothing changed. Checked wires and connections between ECU and PTU again and all appear to be fine. Checked wires between PTU and coil again and all appear to be fine. Checked power and ground again and all....you get it.

So after diagnosing everything I bent all of the female connections so that just in case it had a bad connection I could eliminate it. Then when hooking my MAF back up I over tightened the clamp and....yup.

So I figured WTH and left the maf open from the filter. A little dirt won't hurt it. I go to start it and it turns over like 4 times and GRRRAZZZDFGGERESSSAZZZZZZZZZZ.

Apparently my starter is shimmed too far, not enough and broke or the bolts came loose. AAAARRRRRRRRRRGGGGGGGGGGGGGHHHHHHHHHHHHHHHHHHHHHHHHHHH HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH HHHHHHHHHHHHHHHH HHHHHHHHHHHHHHHHHHHHHHH

[SuperHatch]

Ah, another great day! Swapped plugs and nothing changed. Swapped coils and nothing changed. Checked wires and connections between ECU and PTU again and all appear to be fine. Checked wires between PTU and coil again and all appear to be fine. Checked power and ground again and all....you get it.

So after diagnosing everything I bent all of the female connections so that just in case it had a bad connection I could eliminate it. Then when hooking my MAF back up I over tightened the clamp and....yup.

So I figured WTH and left the maf open from the filter. A little dirt won't hurt it. I go to start it and it turns over like 4 times and GRRRAZZZDFGGERESSSAZZZZZZZZZZ.

Apparently my starter is shimmed too far, not enough and broke or the bolts came loose. AAAARRRRRRRRRRGGGGGGGGGGGGGHHHHHHHHHHHHHHHHHHHHHHHHHHH HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH HHHHHHHHHHHHHHHH HHHHHHHHHHHHHHHHHHHHHHH

If it makes you feel any better I've done absolutely everything you've done trying to diagnose a dead cylinder on my slicktop... no luck at all. I think it's the injector... ugh.

[carmo]

Maybe the injector is stuck open.

[T45]

I wish. The injector is fresh from Deatchworks.

[Carl H]

perhaps you damaged a seal on install?very easy to do with sidefeeds...

[T45]

Maybe god just hates me?

[Q45tech]

A very very rare condition on 90-92 VH45 was that the cam lifter arms jumped off [primarily on #2] and the intake valves wouldn't open.............easy to pull passengerside valve cover to make sure.

[qsiguy]

Now there is some interesting and valuable information! Worth more than my $.02....I was going to ask if you were sure you were troubleshooting the correct cylinder? Stranger things have happened...

[SuperHatch]

Figured mine out... #6 injector registered 40 Mohms (40,000,000)... should be ~12ohms. Hope you figure yours out.

[T45]

A very very rare condition on 90-92 VH45 was that the cam lifter arms jumped off [primarily on #2] and the intake valves wouldn't open.............easy to pull passengerside valve cover to make sure.

Thanks for that tidbit tech! I'll pull it today and see what's up. (fingers crossed).

[T45]

Well the cam followers/lifters are still in place. However I do believe that my timing is out 1 tooth. I set the timing up without the pulley on, just using the keyway on the crank lined up at a 45* angle to vertical, as suggested by the book. However once I lined up the notch on the pulley to the tit on the front cover both cams appear to be retarded one tooth. I got the even's situated, soon I'll take apart the odds and see what they're like.

The reason for the screw up lies on the chain itself. Mine doesn't have any distinguishing silver links on it so I counted links. Works great, except for the fact that I didn't have the crank at true TDC. I hope this is my problem.

Thanks for the feedback everyone! I'll post when I find out what's up with the drivers side. Flying to florida tomorrow for an interview so maybe this weekend I'll get to hammer this baby!!!

[T45]

The timing was off by 1 tooth on all cams. After re-assembling it runs like a brand new engine! So excited!

I'm kind of bummed though because I lost that cool loping sound it used to have, sounded like it was cammed. Oh well, cams will solve that once we can source them.

Got the rad in and plumbed up, another day and we'll be burning them down properly. Vids to follow!

[tmorgan4]

Good work!

[SuperHatch]

The timing was off by 1 tooth on all cams. After re-assembling it runs like a brand new engine! So excited!

I'm kind of bummed though because I lost that cool loping sound it used to have, sounded like it was cammed. Oh well, cams will solve that once we can source them.

Got the rad in and plumbed up, another day and we'll be burning them down properly. Vids to follow!

Great news! Now go have fun with it!

[T45]

Had a great ride yesterday. Car performed exceptional, beyond my expectations. Ran great, sounded totally incredible, handled like a dream...

then something in the engine let go and it's trashed. don't know what happened yet but i'm leaning towards an oiling issue. I have no idea, i don't even want to look at it right now. I just got a job in miami and am moving next weekend so i don't have the time or patience to **** with it right now.

I think i'm just going to park it for a while. Once I get on my feet and get a nice bankroll going I'll get back into it. The transmission was popping out of 4th too so for now I think I'm just going to slowly invest into a low mileage tt trans with adapter, and another engine with a rebuild, build by someone who knows what they're doing. Jeff, you may be getting my Z sooner than expected. lol

I'm so sick to my stomach right now...

[carmo]

That sucks to hear about the car. And too bad 757 is loosing another car enthusiast. Good luck in Miami.

[T45]

Thanks. I pulled some little mazda hatchback kinda thingy like he was sitting still. He pulled around me pretty fast and I didnt think I could catch him but once the rpm's hit 4k I was rolling. It was worth the time, money and effort just to drive it for the 100 or so miles that I did get to drive it. I'll be back...trust me, this car is ****ing incredible!!!

[tmorgan4]

Not at all what I want to hear!!!

I hope it's only something minor but you sound pretty confident that the engine is no good. Keep us updated once you find the time to tear into it. I'll help if I've got any spare parts you can use. I feel the same way on my project all the time. I was so sick of working on mine it has been parked for a month while I search for another car as a daily driver. Then my VH Pathfinder can be a toy and not a daily driver.

[T45]

Yeah it sucks. I was planning on taking it to fla with me but obviously plans have changed. I was so sick when it happened but now I'm not really sweating it. Hopefully it's just parts that I can replace that failed and not problems with the block/heads. It sounded like I threw a couple of handfuls of steel marbles in the heads and crankcase.

I figure once I get some money I'll bring it down to fla and go from there. Mazworx is a few hours away and it would probably benefit both myself and their company to be able to help me build a new oil pan, motor mounts and possibly some head or cam work. I'll be travelling 90% of the time so if it sits for a couple years then so be it. At least I get some good work and they get some measurements to make more swap parts if they like.

You should've heard this thing though, it was such a rush to drive! It accelerated like a freight train and just kept pulling no matter what speed you were at. I couldn't really feel the speed because it sits so low to the ground and handled curves like it was on rails. I can't imagine what it's going to handle like with the suspension dialed in and some good meats on it.

[Q45tech]

We have seen lots of VH45 destroyed from not torquing crank bolt to > 260 lb/ft and oil chain slipping................did you monitor real oil pressure in PSI [no light monitoring allowed] every time you cranked engine and during runs?

Many dealer techs are lazy and get into trouble with chain guides or just replacing front seal. German Gut N Tighten doesn't cut it..always measure.

I losen mine and retighten every 60k.....................now at 18.5 years and 319k.

[darinz]

I feel the pain! I got mine running really well and then in the first competition I dropped into a big hole, bent the chassis and at the same time bent the accelerator pedal, jamming it at WOT! Take into account that if I can get traction my truck will wheel stand in low range first gear and it was in low range first gear and the traction was about perfect!!Anyway on the third attempt I hit the kill switch which allowed me to stop the truck before plowing through the fence and into the crowd!!So I have just restarted the truck after fitting a new chassis which has taken about 300+ hours in the past 2 months to do. The next race is in Rotorua next weekend so nothing like cutting it close!!

I was going to suggest you check injector plug. I had that problem with a brand new plug (3 months old). Took it off, clean it, packed it with electric grease and refitted. In the process one pin got pushed up and gave an intermittent miss! Took a bit to find it and the normal manifold removal in a muddy paddock!!!!!!

[Carl H]

good to know, i nearly maxed out my torque wrench tightening that bolt down...i was almost off the ground trying to make it happen.

We have seen lots of VH45 destroyed from not torquing crank bolt to > 260 lb/ft and oil chain slipping................did you monitor real oil pressure in PSI [no light monitoring allowed] every time you cranked engine and during runs?

Many dealer techs are lazy and get into trouble with chain guides or just replacing front seal. German Gut N Tighten doesn't cut it..always measure.

I losen mine and retighten every 60k.....................now at 18.5 years and 319k.

[T45]

I monitored the oil pressure, it was somewhat erratic but I was leaning towards a cheap gauge and not the pressure itself. I'm not sure if my oil pan, sump or a loose pulley was the culprit. It doesn't really matter now though...

[tmorgan4]

It would be nice to keep it from happening again!!

I forgot that you made the hybrid oil pan. Did you ever check clearance between the oil pickup and pan?