new aspire has no power... sensor problem?

[aithanmier]

hey just picked up a 94 aspire 5 speed 4 door, got it for a song for 500, it is in need of a clutch and has some sort of sensor problem. just thought i'd run it by ya and get some ideas. It has absolutely no power. and i mean not even for a 1.3L. i have owned another 94 aspire and the difference is night and day. this car is struggling to maintain 45mph. i'm gonna run a compression check on it in a min but i'm thinking it's a sensor, no engine codes, but it's using up gobs and gobs of gas. i think it's just running waaayyy too rich and thus not producing any power. any ideas on what sensor to look at? i was thinking the engine coolant sensor and the o2 sensor. i already replaced the maf with my spare of the parts car, not a ton of improvement, but a tad.

[DetroitDon]

Bet it a compression problem........

Don

[aithanmier]

you'd think, but no smoke...it was too cold to check it tonight, i'm gonna get out there tomorrow. i'm thinking maybe the injectors are clogged or one is stuck open or something. if the compression checks out then i'll swap out the injectors and see if that helps.

[DetroitDon]

If the compression turns out acceptable, try 2 cans of Seafoam gas treatment in the tank. Drive it and if it's a dirty injector, or stuck ring, the Seafoam will work wonders......and it's a lot less work that changing out the injectors.....

Good luck,

Don

[aithanmier]

well i ran a compression check on it...well i did the first cylinder. it was at 140 dry, when i went to do the wet test though i couldn't get a reading at all. it would jup to 140 and fall back to 0 immediatly. any clue? i'm sure the compression gauge was in tight, i triple checked it, removed it and reinstalled it. what the hell does it mean? hopefully not a bad tester lol. i think i'm just gonna swap out the longblock with the lower milage one in my festiva (formerly in my other aspire) and go from there.

[FB71]

there's a Schrader valve (like a valve stem) in the end of the compression tester hose. Sounds like its sticking open. Its supposed to let compression pressure into the gage and trap it there, letting you vent it by the manual valve on the gage. The reading shouldn't drop unless that valve is sticking open. Check your gage, and finish the tests. So far, cyl #1 sounds good. Check your cam timing, the belt may have jumped a tooth (or several). I had one back in 95, brand new, doing exactly the same thing. Turned out the cam sprocket was manufactured incorrectly, and the cam timing was off.

[aithanmier]

well i was thinkin maybe the timing but it idles beautifully, wouldn't it run rough if the timing was off a tooth or two? i'm just kinda lost now. no codes, good idle, good compression (so far...gotta finish the test, did another cylinder and it pulled the same thing so it's the gauge), just no power. the plugs are new the cap and rotor look new, ran a can of seafoam through it.

i gotta say though this thing was nasty. filthiest engine compartment i have ever seen. the back seat looked like someone was giving homeless people rides (well actually so do the front seats. just NASTY. finally getting some of it up after my 4th can of stain remover.

[darkdan]

Seafoam is mainly stoddard solvent. Won't do much once diluted in the gas tank.

However, on a warm engine being sucked through a PCV line and allowed to sit for 30 minutes to over night. it does wonders to decarbonize the combustion chamber and intake valves.

If it's a stuck ring try www.auto-rx.com People, I keep recommending this stuff because it works. It will safely and effectively clean ring packs. That's it's main benefit. Any motor with any amount of miles on it could really use. Any car that you are unsure of how the previous owner maintained it really needs it.

Here's an independent test done by a skeptic:

http://rms13.com/

The compression readings are the interesting part.

You can use coupon code ARXDD for a few bucks off a bottle.

[FB71]

well i was thinkin maybe the timing but it idles beautifully, wouldn't it run rough if the timing was off a tooth or two? i'm just kinda lost now. no codes, good idle, good compression (so far...gotta finish the test, did another cylinder and it pulled the same thing so it's the gauge), just no power.

no, a cam out of time will actually make the engine idle very smoothly, to a point. After a certain amount of retard, it will stumble and stall, possibly not even start. It really sounds like the belt jumped one or two teeth. Also, the cam out of time will not set a DTC, even in some OBDII cars. The PCM has to be looking for a cam sync signal, which the Aspire does not generate due to the fact it has a distributor. Cam syncs are typically used in distributorless type ignitions, using one coil for 1 or 2 spark plugs. Can't hurt to check that before yanking the whole engine....

[aithanmier]

well the timing looks ok to me, so maybe a bad distributer? it has the coil built in on the 94 right? i'm guessing the ecm doesn;t check distributer performance, maybe the spark is dropping off as revs increase? the acceleration seems almost normal in the low rpm range, drops off sharply. don't have specifics as the aspire doesn't have a tach yet. i have a spare, so i'll swap it out and check.

[ericsmith32]

After working with my aspire I can think of many things it could be. Have you cleaned the egr valve? On my 94 it only had about a pen size hole left to breath. Idles better, runs better and doesn't do the rev twice thing anymore. Yours idles good though.. The O2 sensor on mine checked good but I noticed a difference after replacing it. I would replace the O2 sensor first. Also get some MMO along with that seafoam and run it for a while. My gas mileage went from 34 to 37 in just one tank on this stuff. Your injectors could be gummy causing the richness. Your right the coil is inside the distributor, if you look at the autozone repair manual section it shows you how to get to it without replacing the entire manual. Do you have a high idle?? Also do you a vacuum tester? Might want to check the fuel pressure regulator also.

[darkdan]

Here's how to clean the EGR:

http://p100.ezboard.com/ffordfestivaaspirefrm68.showMessage?topicID=1.topic

It never got moved to the new board from the ezboard.

[aithanmier]

eureka! it was the distributer. runs like a champ....except now i know how bad the clutch really is. it breaks loose at around 3000 rpm's. so i started replacing the clutch. have to finish it tomorrow, gf is comming over for new years festivities. i just wish i had an axle puller, i swear they make it sound so easy to pull em in the chiltons. "use a crowbar or a large flat screwdriver to GENTLY pry the inner cv joint out of the transaxle. A sharp rap with a brass hammer may be needed" :withstupid:

[Tim]

My gas mileage went from 34 to 37 in just one tank on this stuff. .

I would highly recommend Sea Foam as well. It'll only do your car good.

I was very sceptical of its magical powers until I dumped a can in my tank. Gas mileage went up from 28 to 35 MPG in the city instantly!!!! :shock:

[darkdan]

Oops, I said stoddard solvent....I was wrong.

It's actually pale oil, naptha, and rubbing alcohol mixed in 6:3:1.

BG-44K is now stoddard solvent.

IMO, Seafoam has its uses, but in the gas tank isn't one of them.