car - 1996 Protege DX

me - amateur mechanic with minimal experience

recent work on car - new H2o pump, radiator, distributor, valves (all at the shop) new spark plugs and wires (by me)

current signs that car needs more work -

--check engine light is blinking
--car burns up to two quarts of oil per week
--belt squeals for up to ten seconds when car is started
--lots of bluish white smoke is expelled from exhaust when car is started
--free diagnostic at auto zone gave reading of "crankshaft position sensor"
--car idles much higher than normal (roughly 3000 rpm)
--temperature usually does not register on the gauge (or registers below the gauge) while moving but while idling the temperature gauge registers at halfway
--A/C does not blow hot air anymore

hoping for some suggestions for what to look at...
thanks for any help

 

hi! welcome to the forums. lets start. your car is sick. and i think we should start from the basics. if you want to learn and try fixing your car, cool. if that is not the case, just take it to a shop. the first thing i would do is to check the coolant temperature sensor. if that thing is bad, then your idle speed wont be normal. belt squeals happen because they are loose, adljust it. i would guess it is the alternator belt. just check the tension of all belts. ac not blowing hot air. ok, that is the job of the heater core. but if it is not blowing any hot air at all, it could be the heater control not opening the heater damper, or if just not air at all, a faulty blower fan fuse or blower motor. blue smoke. this coud be painful. only a couple of things here: your piston rings are messed up or the work done to your cylinder head. if that smoke comes out only when you start the engine, then i would think it is a problem of valve seals. but you had your cylinder head done at a machine shop.... but 2 oil quarts of oil a week is a lot. tell us how many miles your car has and do a dry/wet cylinder compression check. record the numbers and let us know.

 

Thanks J,

yes, I am trying to learn; my limitations are time, tools, and my need to keep the car running in order to commute to work.
chances are the car will end up in the shop again, but I am treating that as a last resort both for educational and financial purposes.
I don't have the equipment for a compression test...

the car has 208k on it, the last 5k coming after the work done at the shop (H20 pump, valves, belt, distributor, radiator), and 1k since the plugs and wires.

when it was put into the shop for that work, it had overheated - possibly frying the temp sensor/s?
regarding those - apparently there are two; one is the "sender" which communicates with the gauge, and the other communicates with the computer...
these are pretty cheap ($40 combined) so should I go ahead and replace both? or possibly start with one, then see how it runs? if the latter route, then do you recommend doing a certain one first?

the blue/white smoke (which appears mostly white) doesn't always happen, and never if the car is already warm. it seems like I see more smoke when the ambient temp is cool or cold

one issue I did not touch on in original post: two seemingly random misfires (months apart from one another) while accelerating in second gear;
haven't had this happen since replacing plugs/wires but would it be a good idea to use the lacquer thinner trick anyway?

 

and the fan works...
since I bought the car with 170k on it, the fan has always worked the same. Never had cold air because the compressor is shot but it has always blown hot air until coming out of the shop 5k ago

 

Valves: did they take the head off to replace the valves? Was a head gasket on the itemized bill?
I am just trying to figure out how deep in the engine they went.

There is always a chance that something brakes when you work under the hood. Or something could have been installed incorrectly.

Look at the temp sensors' wire harnesses. It could be they are not completely seated or maybe even mixed up?

Maybe there is not enough coolant in the system?

At this time I would check anything that may have been touched by the mechanics. See if anything is loose or missing. I would not use the lacquer thinner yet. If they removed the head to replace the valves they are clean. I would look for vacuum leaks at the lower intake manifold gasket. There could be a coolant leak into the intake and cause a bunch of trouble.
Go to a parts store and borrow a compression tester. That is key to figure out the cause of the oil consumption.

Report back.

 

if the car overheated, there is a chance of a warped cylinder head (we dont know what kind of job the shop did, if they checked the cylinder head to make sure it was not warped, etc). check the pvc valve (is cheap). get a compression test and you will get a better idea of what is going on. crankshaft position sensor could give you misfires. check the connector, it could be dirty. unplug it and plug it back in a couple of times to see if it is only a bad contact. check the oil for the proper color. if it looks like chocolate water then you have water getting into the oil probably because a bad cylinder head. with the car cold, open the radiator cap and start the car. tell us if you see bubbles in the radiator water.

 

Hey guys (or gals),
Thanks for all the suggestions you have given me. Sorry if I am unable to answer some of your questions. Car is running pretty well at the moment but wanted to log on for some more suggestions, to say thanks, and to update for the benefit of future forum users

I replaced both coolant temperature sensors ( one of which is a "sender")
This fixed the temp gauge on the dash

Idle speed- still inconsistent but fluctuating in new ways:

1. when car idles for more than a minute, idle speed begins to drop
2. when I slow by progressing downward through gears all the way to 1st without skipping gears then shift to neutral, idle speed seems much more normal - this is opposed to when I shift to neutral out of any gear higher than 1st and use brakes to slow down - in this scenario idle speed stays high

original estimate of losing 2 quarts of oil per week is off - dont know how i was so wrong but after keeping closer track my best guess is closer to 1/2 quart per week

white smoke on startup is confusingly inconsistent - doesnt seem to correlate with sitting time, ambient temperature, engine oil level, engine coolant level...
only factor I can pinpoint is that it does not happen if car has been driven within past 6 hours

Car is not leaking coolant

There are bubbles (tiny, nearly microscopic swirling type) in radiator water. Between air filter and engine there is a boot shaped plastic part of the intake - this part is cracked and has been taped over - at risk of sounding like the amateur I am, I suspect that air is leaking out of the intake system due to those cracks - vacuum leak could account for occasional misfires?

Last weekend where I am it rained extremely heavily for 12 + hours. After sitting out in this, car had trouble starting. Hard to describe the sound and feel of the engine trying to turn over, but to me it sounded as if belts were very loose (some squealing, but also some lower pitched warbling). After a few tries I got the engine to turn over but when I pressed the gas pedal I got the opposite of rev - a sound and feel as if car was stalling out. At this point it had stopped raining and after "drying out" for roughly two hours the car started and ran fine).

Thanks for all the help so far and any future thoughts...

 

oil is proper color - doesnt appear to be mixing with water

 

plan to check/clean/replace crankshaft position sensor, clean 02 sensors, get compression test and pvc test and report back

 

fix or replace that air hose that have tape. air leaks after the maf sensor will give you misfires.