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lowviscosity
06-07-2006, 01:07 PM
Alright I was driving monday on my lunch break in the black 1993 240sx coupe (KA24DE) As I drove the engine bogged down, I was hardly getting any power, and when at idle it would vibrat terribly. The engine has not made any noises nor has it ever failed to start, I have changed the oil around every 3,000 miles with Synthetic although I only have had the car for 6,000 miles about. But the car was terrible it would hardly pick up speed, it sounded like sh*t, and at a stop light it idled like a cammed LT4 where my whole car rocked back and forth.

I didn't want to drive much further so I stopped at the mechanics shop off of 3040 and 121 its the Goodyear shop. I stopped in and told them what was happening. They said they could handle it. I dropped the car off Monday... since then it has been hell (without a car that is)

First they replaced the plugs, distributor cap, and injectors, they said it wouldn't turn over after that, guess why it wouldn't turn over.... Because the damn starter case was broke... they showed me a big half of a chunk of case ... now how in the hell did that happen? Bad luck? maybe... scam... I am not saying anything about that assumption yet... I mean this is a 1/4" metal cap basically (measurements could be off but by eye) and its broke. How does that happen when I leave the car there? Where did you take it out to the dirt track or go offroading? but no i'm not laughing because its MY CAR.

Well they say they'll replace the starter on them since it happened while it was in their hands and obviously it wasn't broke nor cracked before I brought it in. Funny...Car still won't fire on that certain pistion hell it doesn't even run. He takes the valve cover off... shows me how the two cam gears are not in time or some bullsh*t... then tells me that the car has "jumped time" ... I think to myself and sort of laugh " you mean my car is like a back to the future car?" of course I didn't say the remark because you know if you make a mechanic mad... (its just like if you piss the people handling your food off) He shows me where piston one should be and how its not at TDC when the cam gears are in the correct position. He says a valve could be bent or possibly a piston rod... because these are "no tolerance engines" Now i'm not a knowledgable person about these cars thats why I'm asking on these forums. It seems I got myself into one of those holes, in which I can't blame anyone but myself. They still have the car and its Wednesday, I feel the longer I leave the car in their hands the more will go wrong with it. But I can't afford to tow it... and I don't have a trailer. I am in the middle of a move right now and need it badly because its my only car at this time. I just have a question... does it sound fishy? or does the terms he used like "no tolerance engine" sound true?

Now I might need a swap if its cheaper... and I am more than willing to work on my own car, since now I have an Apt. where i can get a garage.

tre
06-07-2006, 01:57 PM
Well for it to even jump a tooth on the timing chain. you'd have to have a REALLY loose chain. Not to mention You'd have horribly bent valves probably if it skipped a tooth. Can you take pictures of everything, timing chaing, cams at TDC on the compression stroke.

Hmm when you car bogged down and didnt want to go. Did it sound like it was runnin goff 3 cylinders or maybe even 2?

I don tknow what a KA sounds ilke when it skips a tooth, yet i've never heard of it happening either...

lowviscosity
06-07-2006, 02:03 PM
Chain has never really been loose. I mean you could hear it but i've heard it was a common noise in the front of a 240 and not much to worry about. Just sounded like a light tap and went away when the car was ran. Never have heard much noise from it. Yeah i hear its really tough to skip a tooth. The car sounded like it was running off a few cylinders but not all four... Personally I thought it was fuel injector, spark plug, wires, or fuel filter. I knew it was only running off a few cylinders when it idled because of the rocking....

Isn't that why the chain guard is on the top... to keep it from jumping time.

drew935
06-07-2006, 04:02 PM
Did you even check the MAF? That happened to me when it was going bad.

S14DriftstaiN
06-07-2006, 04:58 PM
what year is your car?are any of the plastic chain guids broken?they may have fallen between the teeth.Its hard to skip a tooth on a timming chain."doubleroller".If they"goodyear"some how turned the key while runnung it in the air and in gear.its in the air to do tests for you running poor problem.this wuold or could explain y the starter case is broken and I would think that if you did"skip a tooth"this would bend valves"and make no compression,It probly would not start.you said it stated up fine till then....IM not sayin they F@cked it up,but thats some strange sh!t.

OdessaS13
06-07-2006, 07:24 PM
first of its not "no tolerence", its interference/ non inteference


When a timing belt/chain breaks, the synchronization between valve
operation and piston location is broken. In a "non-interference" engine, the ranges of motion for the pistons and the intake/exhaust valves are such that they can never make contact with each other. In an "interference" design, the ranges of motion overlap, so in the unfortunate situation when a valve is opening when a piston is at the top of the cylinder, they contact each
other, Of course, when the belt/chain is intact, this doesn't happen, but when it's broken, the crankshaft (and the pistons) is moving independently of the camshaft (and the valves). If the
pistons and valves can collide

anyways back to your problem.
if your problem is what the mech. says youre in for about 1-2 grand in repairs should you choose to leave in their hands...meaning it is cheaper for you to get another DE engine and rent a cherry picker.

I would suggest towing the car home, sitting down, using the search function to see if anyone had the same problems as you and the remedy. if you still cant find it start trouble-shooting fuel/ spark/ crank. All the procedures are in the fsm (you can search for link were to download it from or IM me and ill send it to you)

Tomslide50
06-08-2006, 01:53 PM
From the symptoms you describe it sounds like you have dead miss. this means that 1 or maybe 2 of the cylinders is not producing combustion. This is why you shouldn't take your car to shitty repair places like goodyear. they don't diagnose your car, they tell you you need parts, you buy them marked up, and then they say "well damn that didn't fix it" and they tell you you need something else. Get your car towed and figure it out yourself with the help of people on this forum. Let your motor cool down completely and start it. feel the header primaries as they warm up because one is most likely a good bit cooler than the others because again, it sounds like a dead miss. Rent a compression/leakdown tester and test the motor. If that's good then the issue is fuel or ignition. Since our cars don't have several coils it's usually not common to see one cylinder not getting spark. But check the plug wires where they go down through the valve cover. any white marks where it's arcing to the valve cover? What do the plugs look like? any one of them different? The busted starter case i would probably guess, they worked on the car, and for whatever reason it wouldn't crank so they showed what great technicians they were and hit your starter with a bigass hammer to free it up. This is probably why your case is in two pieces. The people that work at those places generally aren't very knowledgable. they diagnose cars like they did in the 70's and fuel injection scares most of them, so they just throw parts at it. Just say no to bullshit technicians! These guys have to rip you off to make money because they're not smart enough to find the problem in a short enough time to actually make money the honest way. Get your car back! And demand to know why they think it's ok to tell you something's broken and make you pay for it, before they've actually confirmed it to be bad!

daryl337
12-10-2006, 08:39 PM
Well, funny thing is, they shouldnt have been taking the starter off in the first place. Now, as far as the cams go.... did the cams jump in relation to eachother or did the crank timing gear jump? The guides as well as the tensioner take the slack up... I would also look into the chain itself.... like belts... chains can stretch over time... and if you have a stretched chain in combination with bad guides or tensioner.. then that could definately be the problem. As far as the valves being bent... if I remember correctly... 1 tooth on the camshaft is about 5-7 degrees... so it really depends on "how much" they skipped in timing. You might not bend a valve with a 5-7 degree variance, but it will definately make for a shitty idle as well as a loss of power.

ledzeppelin240
12-10-2006, 09:05 PM
Sounds like you got scammed by complete idiots....If your valve timing was 'retarded' by skipping that would explain the symptoms you were describing. It's hard to say what it could be without actually taking a look at the car.

I would say valve timing out. Starter casing broke due to siezing engine??? So many possible reasons...

aznpoopy
12-10-2006, 10:16 PM
6 month old thread

jump teeth usually doesn't happen
but i don't see why it couldn't

hellbilly1342
12-10-2006, 10:53 PM
i have seen jumped timing on a couple M3's being a BMW technician. it's usually caused by over reving the engine from downshifting. it causes a backlash of the chain and in the 2 cases i've seen the chain smacks the valve cover and puts a nice big hole in the valve cover and marks along the inside of the head.

arlocks13
12-11-2006, 01:13 AM
something similar happened to me the symtoms sound familiar, Does your car run yet? If not try checking the fuel pump mine went out of me while I was driving in the mountains. I was pushing pretty hard tho, i duno how it would happen on normal driving unless it was just stock and going out on you from old age... but if your cars runs right now shitty or not it wouldn't be the fuel pump.