Hey guys,
I'm new to the forum and need some help figuring out whats going on with my neon. It is 97 plymouth neon with 137k.

Heres the problem.

- This just started recently but when driving especially when going up hill, I will loose power and as I try to push the pedal furhter to the floor the car jerks (sometimes very violently) and then I hear a Loud CLACK noise. At first I thought this might be a problem with the tranny, but my bro suggested maybe its a fuel problem like a plugged filter or bad fuel pump? what do you guys think?

- There has also been ocassions where when i first start the car and put in reverse it makes the same jerking motion (not as violent) like when I'm driving up hill, but I dont hear that loud clack. Which makes me wonder if it really is a fuel problem

I ran the check engine codes but dont know what to make of them:
Code:
11
12
37

Any help is Very Appriciated
Thanks

 

11 Timing belt skipped 1 tooth or more from initial learned value, Intermittent loss of either camshaft or crankshaft position sensor, No crank reference signal detected during engine cranking

37 Torque converter clutch solenoid circuit, or park/neutral switch failure; might be low voltage on transmission temperature sensor

12 Direct battery input to PCM was disconnected within the last 50 key-on cycles

Try scanning with an OBD11 scanner It should give you more detail.

 

thanks will, do

 

When my code 11 popped up, my Crankshaft Position Sensor was bad. It sounds like yours may be going bad. They are easy to replace and not that expensive either. The code 11 will also pop up if your Camshaft Position Sensor is going/gone bad. I would make sure to check both of those out. The Haynes manual tells you how to check them both out.

Also, since you have 137K on the car, when was the timing belt replaced? If the answer is never, then that could very well be your problem and you may have had some slippage in timing. Hopefully you don't have enough slippage to cause your valves to be way out of whack, but when you stated you heard a loud CLACK, I suspect that could be as when one of your valves made some at least some contact with the piston. You need to park that thing and check it out before you end up rebuilding the engine. These engines are interference engines and when the belt goes, it can wipe out valves, pistons, etc. When the belt on my car went out, it took out the intake and exhaust values on my #1 cylinder, but I rebuilt the engine anyway since it had 157K on it.

My suggestion is to quickly check the timing on your car. You can do this easily without having to remove anything other then a spark plug and a rubber plug from the front of the timing belt cover. You remove the #1 cylinder spark plug. Find/Get a long (about 10-12 inches or better) round metal shaft to put into the hole you just opened. I use a 10 inch long 3/8 drill bit I already had lying around). Get a friend (or you can do it yourself, but don't stick the shaft in and just leave it as you can lock up your motor) to help you turn the crankshaft pulley bolt until the #1 cylinder is at TDC (top dead center). You know you are at TDC when you can turn the pulley a little bit either way and the piston goes down. At this time, check the timing mark on the camshaft by shining a light into the hole you just opened in the cover. If the mark lines up with the mark on the cover, you are in time. If not, you have slippage and need to address this mucho pronto! Do not drive the car anymore until you fix this as you are asking for trouble and mucho dinaro repairo.

If there was slippage in timing, then I also recommend you go ahead and pull the head and check to make sure that 1) you don't have some valve damage and 2) the pistons do not have damaged faces due to contact with valve(s). If there is damage, then you are looking at an engine rebuild and sending the head to a machine shop for a rebuild.

Even if you are in time, if the timing belt has never been replaced, it is WAY past time to do so. Most everyone will recommend that you not only replace the timing belt, but the idler pulley and the water pump too. Both are cheap and if you do them both, neither one will be a future risk to wiping out a new belt and/or engine.

 

You can check for valve damage without removing the head. If, as in you case the timing belt is still in place a compression or a leak-down test will confirm valve condition. If the timing belt is broken you can still do a leak-down test by removing the rocker arm assemble so the valves are closed.

When I had the belt done they assembled it 1 tooth out and the only way I could tell was that it gave a timing belt out by 1 or more teeth, this only happened at high revs.

I’m also leaning towards a bad cam sensor placing the engine into limp or (limp home) mode.

 

To do a compression check, you have to "crank" the car (x4) and if there is timing slippage, I seriously do not recommend doing that. - at all - period. Even if the contact occurs only at high revs, that is not a chance I would take.

Again, assuming there is timing slippage, if he did have contact, most likely one of the valve stems got bent during the contact and will need to be replaced anyway. Add to that, the car has 137K on it. Getting the head serviced is a good idea and really not that expensive. When my head needed it, the shop did the whole job for $150.00 - all I had to do was give it to them and pick it up. Remember, I also needed two new exhaust values, 1 new intake valve, 1 new exhaust rocker, 1 new intake rocker and it still only cost $150.00.

Look, you can spend a little more and have a reliable driver for a good long while, or you can nickle and dime the repairs. Your choice. If the car just is not worth it to you, go cheap, get it running, sell it and run. If the car is something you would like to have around for a long time, I would go ahead and rebuild the darn thing.

My 1995 Neon is most likely worth about $500 actual dollars. I could maybe get $1500 for it because I just finished rebuilding the engine and putting a new clutch in, but I would have to find someone who I could show this too). I certainly could get more selling the thing as parts. The car itself is solid and rust free and other then the paint looking like it has dandruff and faded in places, and the extensive hail damage making it look like it has dimples, who cares? I like the car.

I got the car for free from a friend who left it on the side of the road and said if I wanted it, tow it home. I have spent approx. $1000 getting it back in running shape, but included in that price is a new starter, new alternator, a complete engine rebuild with all new parts and such, a new clutch, a new passenger mirror, a new rearview mirror, two new tires, a new taillight, two used window crank mechanisms (mine rattled like a B@##$). And, in fact, I had to rebuild the engine twice because I had issues with the first rebuild (damn front oil seal popped out of oil pump and spewed oil everywhere and caused bearing damage) that caused me to have to get oversized pistons, rings, engine bored .5mm over (.020), crank turned and oversized bearings too along with another gasket kit.

What did I get for my efforts? A fun time working on my "project car" in my new garage, a daily driver that should last me a long time (at 35 mpg btw - wooohooo!), is fun to drive, costs me little to insure, almost nothing to own, and I can laugh all the way to the bank each time I DON'T have to make a car payment! Yea!

 

A leak down test will confirm (good or bad) whether or not you have valve issues (bent or gummed up) and can be done without trying to "crank" the car, but unless you have the equipment to do it, you will have to find someone who does. If you can do this (or have it done) I do recommend this as you will not further damage the car doing it, and has the added advantage of giving you a really good indication of the need to have the head removed and redone.

 

You can build you own leak down tester.In the photo of mine, the fitting between the two gauges is plugged and then drilled with a 1mm or .040" bit to calibrate the air flow.

http://www.supraforums.com/forum/sho...d.php?t=520536
http://www.motorcycleproject.com/mot.../leakdown.html

 

Thanks guys for the info,

The head was replaced with the timming belt around 100k. Also the Cam sensor was replaced about 6 months ago

I'm also noticing that the car is bogging down alot, I manually checked the fuel pressure (without a guage just visually) and the gas would just kinda pour out as if it wasn't under very much pressure. Because of this and the bogging down I bought a fuel pump and filter. When I get them installed I'll post back, in the mean time I will check timming etc. and post back

Oh another quick question I was told that the #1 o2 sensor was replaced with a DOHC model even though the car is SOHC would this make a difference in performance or cause problems?

 

I did not think there was a difference in the o2 sensors being DOHC or SOHC, and it turns out that I was thinking correctly. Just to be sure, I went to the autozone website and searched for a 1997 DOHC and SOHC engined car, and the part numbers they gave were the same. Therefore, unless you are getting a o2 error code in your PCM, you are fine.