94 Metro engine problems

Hello,
I have a 1994 Geo Metro, 128,000 miles, 1.0L 3-cylinder engine, automatic transmission, with throttle body fuel injection. The car was running fine until on the way home from work it started to lose power. I was able to get it home only by keeping the accelerator to the floor. These are my current symptoms: 1. Starts hard. 2. After starting it has a rough idle. 3. If you try to "blip" the accelerator either during idle or while driving, it stalls. 4. It tries to cut out when you shift into gear. 5. I can hear light backfiring when letting off from full throttle. 6. It stalls when accelerating from a stop, unless I power-brake it to get the rpm up. It runs ok at mid throttle range but will not go above 55mph on a flat, straight stretch of road at full throttle. Low end throttle it stalls, high end throttle lack of power. I've verified the timing setting, replaced the plugs, wires, and fuel filter with no success. No engine codes stored. Any ideas? Thanks

History repeats itself.....

Look at "HELP NEEDED IN A HURRY! Metro 3 cyl DIED this morning, won't restart" at my post (DoctorBill).

Whenever someone presents with a post like yours, I try to convince them to
do a COMPRESSION CHECK.

Maybe I am being obsessive-compulsive, but that test can eleiminate or zero in
on many problems.

If you have burned thru an Exhaust Valve, usually number 1 cylinder on these
3 cylinder Suzuki engines, you get your symptoms.

It happened to me at 157,000 miles with exactly the same engine ('93 Metro).

At least that is what I have gathered by reading on this Forum....

Chime in folks!

DoctorBill

Yes, check the compression.

Q

Sounds like the fuel pump is starting to fail. Exact symptoms when my fuel pump in my 92 Beretta failed.

History repeats itself.....

Look at "HELP NEEDED IN A HURRY! Metro 3 cyl DIED this morning, won't restart" at my post (DoctorBill).

Whenever someone presents with a post like yours, I try to convince them to
do a COMPRESSION CHECK.

Maybe I am being obsessive-compulsive, but that test can eleiminate or zero in
on many problems.

If you have burned thru an Exhaust Valve, usually number 1 cylinder on these
3 cylinder Suzuki engines, you get your symptoms.

It happened to me at 157,000 miles with exactly the same engine ('93 Metro).

At least that is what I have gathered by reading on this Forum....

Chime in folks!

DoctorBill


Sorry, I forgot to mention that:uhoh:. I ran a compression check last Sunday (2 days after the car became ill) and it was 180 pounds across all three cylinders. I had heard the Metros were notorious for burned valves so I checked that ASAP. Thanks.

+1 With the abruptness of the problem and symptoms given, we need to eliminate fuel delivery issues.

What you need to aquire is a fuel pressure guage that you can install inline with the fuel feed line (larger diameter) at the TB via a T fitting. I'll take a picture of the setup I use and post back tomorrow.

Check the hose and connector to the MAP sensor. Make sure your coil wire is well affixed to the cap and esp. to the coil.

-MechanicMatt

+1 With the abruptness of the problem and symptoms given, we need to eliminate fuel delivery issues.

What you need to aquire is a fuel pressure guage that you can install inline with the fuel feed line (larger diameter) at the TB via a T fitting. I'll take a picture of the setup I use and post back tomorrow.

Check the hose and connector to the MAP sensor. Make sure your coil wire is well affixed to the cap and esp. to the coil.

-MechanicMatt

Matt,
Thanks for all the info. Where can I purchase a fuel pressure gauge? Will a vacuum type T-fitting work for this application? Coil wire is good to go. Hose to MAP sensor is pliable with no cracks. Thanks, again:)

-Rem

http://i77.photobucket.com/albums/j64/isc20/017.jpg

This fuel pressure guage was purchased at sears, you can find similar tools at your local auto parts supply I'm sure, autozone, kragen/shucks, o'reily's, pepboys, etc etc...

I cut the threaded fitting off the end of the guage and stuck a T-fitting (vacuum type stuff is fine) in the end of it. Then took a length of appropriate sized hose and wrapped it around another leg of the T (proper I.D. escapes me, 3/8ths, 5/16thsish). Then when you go to take your reading you disconnect the fuel supply (larger diameter) stick it onto the unused leg of the T fitting, clamp it down, then attach the hosed end of the apparatus to the throttle body and clamp it down. Pretty easy stuff.

Connect guage and:

a) Get a reading with the key-on engine off (KOEO) and see that the fuel pressure holds steady (losing no more than a couple psi over 5-10 minutes)
b) Get a reading with the engine at idle.
c) Rev the motor a few times and see that the guage reacts positively (displaying slightly higher fuel pressure) to throttle snaps.
d) If so inclined, tape the guage to the windshield and take a quick drive and see if any sudden low readings appear with driveability problems.

-MechanicMatt

P.S. The hose on the fuel guage will have a pretty small internal diameter. I had to literally drill the hose out, and use some spray lube in order to get the T fitting inside the fuel guage hose.

Caprice,
Thanks for the pic. I'll put one together today and run the tests.

-Rem

http://i77.photobucket.com/albums/j64/isc20/017.jpg

This fuel pressure guage was purchased at sears, you can find similar tools at your local auto parts supply I'm sure, autozone, kragen/shucks, o'reily's, pepboys, etc etc...

I cut the threaded fitting off the end of the guage and stuck a T-fitting (vacuum type stuff is fine) in the end of it. Then took a length of appropriate sized hose and wrapped it around another leg of the T (proper I.D. escapes me, 3/8ths, 5/16thsish). Then when you go to take your reading you disconnect the fuel supply (larger diameter) stick it onto the unused leg of the T fitting, clamp it down, then attach the hosed end of the apparatus to the throttle body and clamp it down. Pretty easy stuff.

Connect guage and:

a) Get a reading with the key-on engine off (KOEO) and see that the fuel pressure holds steady (losing no more than a couple psi over 5-10 minutes)
b) Get a reading with the engine at idle.
c) Rev the motor a few times and see that the guage reacts positively (displaying slightly higher fuel pressure) to throttle snaps.
d) If so inclined, tape the guage to the windshield and take a quick drive and see if any sudden low readings appear with driveability problems.

-MechanicMatt

P.S. The hose on the fuel guage will have a pretty small internal diameter. I had to literally drill the hose out, and use some spray lube in order to get the T fitting inside the fuel guage hose.

Matt,
I just finished taking the readings. (1) Key on, engine off-25psi
(2) Idle-22psi
(3) Throttling- 22-32psi responsive
Would this suggest the fuel pump is OK? Thanks.

-Rem

That definitely seems low to me, but I can't recall where our numbers should be. I think I recall numbers in the high 30s/low 40s the last time I checked fuel pressure on a metro. Maybe someone else here has the spec. Monday I'll look through my books and tell you what they say if noone else chimes in.

Pinch off the fuel return hose and see if that brings the numbers up at all.

-MechanicMatt

That definitely seems low to me, but I can't recall where our numbers should be. I think I recall numbers in the high 30s/low 40s the last time I checked fuel pressure on a metro. Maybe someone else here has the spec. Monday I'll look through my books and tell you what they say if noone else chimes in.

Pinch off the fuel return hose and see if that brings the numbers up at all.

-MechanicMatt

The 3 Cyl Metro's are TB (Throttle Body) injected engines. Fuel pressure on your car is Normal. Fuel pressure readings in the in the High 30's/Low 40's with the KOEO are normally found on "Port Fuel Injected" engine setups.


Specifications for a 1994 Geo Metro Fuel Pressure:

1. Key on engine off .......(23 psi) 160 kPa
2. Engine Idling .............(22-31 psi) 160-210 kPa


Fuel Pressure & Regulator - Specifications Revised.

Group Ref.: 6E - Engine Fuel & Emission

Bulletin No.: 416521

Date: August, 1994

SERVICE MANUAL UPDATE

SUBJECT:
SECTION 6E2 - REVISED FUEL PRESSURE SPECIFICATIONS

MODELS:
1989-94 GEO METRO WITH 1.0L ENGINE (VIN 6 - RPO LP2)

Circuit Description:

When the ignition switch is turned to the "ON" position, the Engine Control Module (ECM) will turn "ON" the in-tank fuel pump. It will remain "ON" as long as the engine is cranking or running and the ECM is receiving ignition reference pulses. It there are no reference pulses, the ECM will shut "OFF" the fuel pump in about 2 seconds after ignition "ON" or engine stops.

The fuel pump delivers fuel through an in-line filter to the TBI assembly. The integral fuel pressure regulator controls system pressure to about 160-210 kPa (23-31 psi) with ignition switch "ON" (KOEO) and to about 90-160 kPa (13-22 psi) with the engine idling at normal operating temperature. Excess fuel is returned to the fuel tank through a separate line.

My next thing to do would be (since I have a spare) replace the MAP sensor and check all over to make sure there are no vacuum leaks ( hoses that fell off / broke ), especially around the firewall where the metal vacuum hose connector is bolted on, and the hoses to the purge canister. Seems like your compression is fine and fuel pressure is good as well. I would also make sure the distributor is not loose.

Has anybody mentioned changing the FUEL FILTER?

How long has the current fuel filter been in there?

If the fuel filter is plugged, it can cause all sorts of problems and still give you
a good fuel pressure reading - because the plugging is often 'intermittent'.

If you are going to change it, why not bypass it next to the fuel tank
(use a section of fuel tubing) and put it up front in the engine compartment
between the firewall and the fuel input barb on the TB...?

Makes for nice, easy changing later......no more gasoline all over you
while laying on your back!

DoctorBill

In the original post, remington7 said he replaced the fuel filter...LoL

OH YES!

I read his original post to check and still missed that....old eyes.....

Sorry.

DoctorBill

Okay. Seeing how my last post on this thread seems to have been ARBITRARILY deleted after I spent A LOT of my own TIME trying to write an informative response to this individuals' PROBLEM, I'll have to respond to Remington in PM. Sorry guys, must have been because I sourced pictures from a site that WASN'T AUTOMOTIVEFORUMS.com. The MOD who did it didn't even PM me this time offering an explaination (last post I got deleted was in the caprice section). :banghead:
--------------------------------------------

In any case, the condensed version:

a) Unplug the ECT located in the Throttle body near the throttle cable. I've had clogged coolant passages in a metro exactly like yours (94 3cyl auto) cause problems under acceleration, rough idle, and hard starts. Unplugging it immediately and dramatically improved these symptoms, which lead me to the clogged passages in the TB. I'll PM you a LINK to a picture if you need one.

b) A misadjusted TPS can definitely degrade performance, as well as cause rough/wandering idles. So this may be something to look into. Again, if you need a picture I can't post it here short of downloading it and uploading to (insert photo-hosting website).

-MechanicMatt

P.S. I'm going to start saving my posts (in an unmentioned word processing program) in case I get CENSORED off the map.

Gentleman,
An update on my problem. I metered the throttle position sensor and according to my Hayne's manual, it was in spec. MechanicMatt, I will check the items you have listed in your last post and will get back to you. The pictures you spoke of in your last post would be appreciated. As for the MAP sensor, I could not get a read on it and I do not have a spare to swap out. I will check the local scrapyards to see if I can find one. One further question though, if this could possibly be a backpressure problem...how can I check engine backpressure and what is the acceptable backpressure PSI for this engine?:uhoh: The reason I ask is, I thought I could hear an exhaust leak the last time the car ran...so...I plugged off the tailpipe, and the car continued to run. Hmmm? Thanks again for all the informative replies.

-Rem

Could be your cat melted down. Unbolt the exhaust at the manifold and drive it around the block to see if it's any better.

91Caprice9c1 - just trying to help....

If you upload your pictures to Photobucket.com or ImageShack.us, you can then
post the "links" from them as I and others here do and no-one should bother you.(?)

That way, the links load without using storage space on this forum's Hard Drive...

Or is this something you already knew about?

DoctorBill

PS - I have not been doing any 'moderating' so I don't know what is going on.

Gentlemen, Update: I ran the check on the coolant temperature sensor at the throttle body with no changes. I unplugged sensor and car still ran poorly. Currently though, if I try to start the car cold, it starts, then quits and will not restart...unless I pull the fuel injection fuse and crank the engine to purge the throttle body of fuel. After replacing the FI fuse then cranking the engine it will only then start and keep running, but still runs poorly until it warms up. As a side note, I completely plugged the tailpipe off with a sock (while the car was running) and it continued to run until I shut it off. Is this normal? Still no stored codes. I'm not sure what to try next and I don't want to take it to a mechanic that may play the old "replace and pay" until they find the problem. Thanks. -Rem

Looks like something is amiss with your exhaust system....

Do you have a catalytic converter?

Exhaust gas has to go somewhere!

If you plugged the tail pipe and it still runs....you have a humongous leak!

Is the engine loud? Like maybe with a leak BEFORE the muffler?
Maybe a leak after the muffler but before the Cat Converter....?

I think a visit to a local Muffler Shop of good repute is called for.....

Expect to pay for a muffler, some pipe and/or maybe a catalytic converter.

Once that is taken care of, if the car still acts up - onward to the next thing.

How about the O2 Sensor....?

The PVC Valve, the EGR Valve (carboned up?)

Do you have a vacuum leak?

DoctorBill

GM thank you for correcting me.

I think woodie is on the head of the nail here. Unbolt the exhaust from the manifold and see if the car wakes up.

Stuffing a sock in the tailpipe doesn't tell us anything useful, except that there is not enough air to push it out (which I would definitely think there should be). Exhaust restriction? Possibly. Do as Woodie said.

-MechanicMatt

Looks like something is amiss with your exhaust system....

Do you have a catalytic converter?

Exhaust gas has to go somewhere!

If you plugged the tail pipe and it still runs....you have a humongous leak!

Is the engine loud? Like maybe with a leak BEFORE the muffler?
Maybe a leak after the muffler but before the Cat Converter....?

I think a visit to a local Muffler Shop of good repute is called for.....

Expect to pay for a muffler, some pipe and/or maybe a catalytic converter.

Once that is taken care of, if the car still acts up - onward to the next thing.

How about the O2 Sensor....?

The PVC Valve, the EGR Valve (carboned up?)

Do you have a vacuum leak?

DoctorBill
Update: Another symptom to report. All previous problems remain the same but...I drove the car to work the other day (7 miles each way) since it had set for over a week, on the return trip that night it took me 45 minutes to get the car started and frisky enough to stay running. On the way home, I kept having to drop to a lower gear to bring rpm's up enough to get home:banghead:. After arriving home (7 miles took 30 minutes, normally takes 10 minutes), I barely made it up the small rise into my driveway (lack of power). I parked, left the engine running and popped the hood to check for exhaust leaks and :eek: the exhaust manifold was GLOWING. I thought the poor little Suzuki was in meltdown. My marbles have all gone missing:screwy:. Bring on the ideas fellas. Thanks.

P.S. 02 sensor-6 months old, vacuum check good (both with gauge and "WD-40" test), PCV valve-last oil change

-Rem

If you have a spare MAP sensor, give it a shot. You can find them in the junk yards for about $10.00 I always carry a spare. Dont' buy a new one they are to much $. Next then is to check your TPS with a volmeter. After you have checked those two things, make sure all your vacuum hoses are hooked up correctly as per the underhood emission sticker.

I know you checked the fuel pressure, but do it a again when the car is acting up. I had a geo that wouldn't barely make it up steep hills, and it turned out to be the fuel pump.

Glowing exhause manifolds sometimes occur with a intake vacuum leak or running to lean. (check again for intake vacuum leaks, if none, maybee your MAP is bad causing the car to run lean??

good luck

I barely made it up the small rise into my driveway (lack of power). I parked, left the engine running and popped the hood to check for exhaust leaks and :eek: the exhaust manifold was GLOWING. I thought the poor little Suzuki was in meltdown. My marbles have all gone missing:screwy:. Bring on the ideas fellas. Thanks.
Is the "Check Engine Light" in the dash staying ON when you drive the car?

Glowing exhaust manifold is an indication of:
1. A "Lean" air/fuel mixture in the engine.
2. Incorrect ignition timing.
3. Clog /Obstruction in the exhaust system.
4. Broken exhaust manifold bolt letting air enter into the exhaust port from the outside (Usually hear a "Ticking" noise also with this problem).
5. O2 Sensor bad (which would set a code 13 error code)

Since the car has a major loss of power along with the glowing exhaust manifold.....

1. Incorrect ignition timing.
2. Clog /Obstruction in the exhaust system.

Have you tried the suggestion Woody made yet? (Could be your cat melted down. Unbolt the exhaust pipe at the exhaust manifold and drive it around the block to see if it's any better.?)

Is the "Check Engine Light" in the dash staying ON when you drive the car?

Glowing exhaust manifold is an indication of:
1. A "Lean" air/fuel mixture in the engine.
2. Incorrect ignition timing.
3. Clog /Obstruction in the exhaust system.
4. Broken exhaust manifold bolt letting air enter into the exhaust port from the outside (Usually hear a "Ticking" noise also with this problem).
5. O2 Sensor bad (which would set a code 13 error code)

Since the car has a major loss of power along with the glowing exhaust manifold.....

1. Incorrect ignition timing.
2. Clog /Obstruction in the exhaust system.

Have you tried the suggestion Woody made yet? (Could be your cat melted down. Unbolt the exhaust pipe at the exhaust manifold and drive it around the block to see if it's any better.?)

Rat,
Car has no codes stored. I unbolted exhaust pipe at the manifold for a test drive and the car would not stay running, so I bolted it back up. I checked the timing again (with the rough idling still present) and it was 5* BTDC which is what the emission sticker shows as correct timing. Could the rough idling cause an erroneous timing reading? Also, could a malfunctioning stator cause the symptoms I am encountering? Thanks.

-Rem

Fellas,
I think I may have found the problem. I have a blown exhaust seal (doughnut gasket) between the cat pipe and exhaust manifold. The car acted like this before when the exhaust pipe broke in two. I should have remembered this:banghead:. The old exhaust seal is pretty well shot but I have a problem...it seems to be fused to the exhaust manifold pipe:disappoin. I have scraped on it but it doesn't seem to help much. Does anyone know of a better way to remove this seal from the manifold? Thanks

-rem

In the old days a glowing manifold was a sure sign of slow timing. Since you haven't changed it, maybe it has jumped time. Put a light on it. You are looking for say 20 degrees off. Then I'd still explore a stopped up exhaust. Heats gotta go somewhere.

nobuddie,
I found the problem (see post #28) but I'm trying to remove the doughnut gasket from the exhaust manifold. Any ideas? Thanks.

Hammer + Chissel

-MechanicMatt

are you sure its not made on the manifold? If its not, a heavy duty screwdriver or punch and a hammer.

are you sure its not made on the manifold? If its not, a heavy duty screwdriver or punch and a hammer.


No, it's a seperate seal. I'll probably take it off the car to make getting at the old remnants easier. Thanks.:grinyes: