cranks but wont fire...what the eff!!!

[xxtoobsxx]

So I tried the club lexus boards and people just read and no replies. Hopefully someone here can help. A while back maybe 3 months ago my passenger side camshaft bolt broke after my car overheated and. The car ran barely when cold and would die when warm. I fixed the broken plastic water neck and started it worked fine, idled fine for 30 min. Drive it to auto zone to return some parts I didn't need and 2 miles away in the autozone parking lot it dies. As soon as I take off the pass side spark plug cover to check spark I see the cam gear is loose. I figure hmm...weird. I tow the car home break down that side and the gear falls off. So I buy a new (used) intake camshaft with pulley bolts and pickup. The journals are good and oem spec form a low mileage motor. So I put the cam in alining the 4 dots (I followed the diy on lextreme). Intall timing belt all marks are dead on spot. Put a brand new battery in and go to crank it and it doesn't start. Cranks but no fire....anyone have any ideas?

 

[xxtoobsxx]

Sorry for the long story too...the car is a 93 sc400. If I remember correctly they have non interference heads!!!

 

[xxtoobsxx]

Sorry one more thing...when it cranks a few times I get a puff of smoke from the intake!

 

[Zuffen]

Sounds like you have a wiring problem in that distributor.

Are you positive you plugged all the wiring back in?

And are you sure the timing isn't out by 90 or 180 degrees?

 

[xxtoobsxx]

Finally a response. I set the crank to 0, then did the cams. I put each cam gear lined up with the the cam marks with the marks on the back plates. Ill double check later on, and for spar too!

 

[xxtoobsxx]

A lil update: So car still isnt running. I took it to a shop i was 1 tooth off on the timing, they resent it and still nothing. Car cranks but does not fire. Its almost as if it isnt cranking fast enough. The starter is not the prob as it will spin it no prob. New battery and everything, and fresh gas. Plugs are gapped correctly and are new, as is all ignition parts. I dont kow what else to do. I am thinking about putting in a 95 1uz, will this bolt in no prob? I keep getting mixed reviews on CL and not much on the subject when searched here.

If i dont find a solution soon I may have to sell the car as is with system, suspension and wheels and what not.

 

[spf_lexus]

Are you getting any check engine codes? If so start there.


You stated that your pass. side cam bolt broke.. can you elaborate a little?

 

[xxtoobsxx]

No codes at all, timing is spot on. Everything is working fine and it still wont crank. compression numbers were all even in the 200 range. I dont remember exact comp numbers but they were not low by any means!

The car overheated last year and i hadnt noticed until i pulled into the parking lot at work where the gauge went to hot and all hell broke loose. Parked it, it cooled off and went to work. Came out and cranked it and it ran...well it idled fine. Had it towed home just incase and found a crack in the upper waterneck/thermostat housing. Replaced all parts, flushed the system and refilled and purged it of air. Turned it on and let it idle for 20 min and it never overheated. Decided to drive 3 miles to autozone to take back the old oil i had just taken out after i did a flush and right as i pull into the lot the car is idling like crap. Park, leave it running and pop the hood and i hear a clanking. so i shut her down, have her towed home. I decide to trouble shoot 2 days later and when i took off the spark plug covers to check plugs ll was well. I figure maybe it jumped timing since it over heated. Just at that moment i took off the associated placstics for the pass cam bank and the cam gear falls off with the bolt head stuck to it.

Turns out the bolt had sheared off and whatnot. So i try to extract the broken bolt and i get it, but realize the alignment pin was broken too. I tray to get that out with no avail and buy a replacement intake passenger camshaft (with gear and pickup). Bolt all the parts on as per the DIY on here. SNug everything down go to crank her and nothing. All i get it a puff of while smoke out the intake.

any ideas now?

 

[xxtoobsxx]

I just did that. Even had my mechanic do it again and we each checked it. Everyone is dumfounded. Is anyone here in the socal area that wants to maybe help me?

 

[sideshow]

y the hell u spending money on this fukt enigne then
for 500 bucks buy a 2nd hand motor and dont bloody touch it
and take car eof it heheeh

 

[xxtoobsxx]

I actually did buy a new motor allready. I just wanted to see if anyone knew what was up. I wanted to see if lextreme wanted it for parts for a store credit or maybe even some parts. Since they charge a core charge add up the core charges and hook me up with some parts or something...

 

[converted]

to spf_lexus, that was my engine which had the passenger side cam bolt break due to seized camshaft.

Its very hard to determine over a forum what could be wrong with the engine...in my case I had alot of suggestions as to what it could have been but who would have guessed it would have been a seized camshaft.
Of all things my engine idled reasonably well on cold startup....this was all on 4 cylinders only firing.

 

[spf_lexus]

All I can come up with would be that the seized cam might be twisted slightly, which would throw off timing big time and I suppose it's possible that 1 bank has it's timing thrown off compared to the driver side. If it's twisted, the cam pulley will still be timed with the timing belt (no skipped teeth) but the cam itself could be thrown off. I broke an intake cam trying to get the pulley off at a machine shop and it didnt take much tq to damage them. If this sounds similar to your scenario, a used set of cams/caps could help narrow the problem down.

Hope you find the root of the problem.

 

[xxtoobsxx]

So do yall think that maybe Since i only replaced the Intake camshaft maybe the exhaust camshaft is twisted and could be thwarting the whole thing? I feel like the motor itself is still good. If i can keep the motor that came with the car that would be ideal!!

 

[sideshow]

double check compression
this will tell u if everything is ok
or better still a leakage test

and double check the rotor buttons havnt been put on back to front
its easy to do as i wired up a car ages ago and customer fitted one rotor 180 degrees
out and broke the locating tab on the rotor
**king took me 4 hours to figure why it would not start
and if this fixes the problem u owe me a bottle of burbon heheheheh

 

[xxtoobsxx]

Wait..rotor buttons? Do you have a picture of this?

 

[sideshow]

Pics why
have u got 200 bucks to give me to strip a perfectly good motor
if u don't know how to build an engine don't touch it
hehehee
really it's a 15 minute job to check them

 

[BigKriss]

Did your kid get hold of your log in details here Sideshow ? Just checking mate..

 

[sideshow]

he prob did
only 2 year old i know with an iphone heheheeh

 

[xxtoobsxx]

I have built motors, Just never heard of rotor buttons. All have been distributorless igniton, Except my old 351c that i had a pertronics system but had points before hand!