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cold start; geo wont start when cold
Topic Started: Feb 27 2009, 09:09 PM (4,158 Views)
suzukitom
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Tom

Bank2me
Aug 16 2017, 07:41 PM
Yep fully warmed up. Throttle wide open battery charged. And yes I cranked a while on each cylinder. Fuel injection fuse and relay removed. What do you fellas think? I think it's time for a cylinder leakdown test. But i have never performed one before.
Do you have a leak down tester? Actually, it may be more useful to add a capful of oil into each cylinder through the spark plug hole(s) and perform a wet compression test. This will provide some information on your piston ring condition.

The readings, (140/115/123) if accurate, are on the low side, but not alarming on a well travelled Metro. The differences in compression readings between each cylinder are also concerning, as it indicates a +/- 20% variance, but in my opinion, this is a secondary concern that is not related to your 'too low'' cold idle speed symptoms. A properly adjusted throttle body,TPS and functional ISC should be able to produce a fast idle even on a worn engine during a cold start.

How does the engine perform overall? Does it accelerate smoothly? Do you notice any smoke from the exhaust or note any oil consumption? Have you had a chance to calculate your fuel mileage yet?



Edited by suzukitom, Aug 16 2017, 08:31 PM.
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Bank2me
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suzukitom
Aug 16 2017, 08:31 PM
Bank2me
Aug 16 2017, 07:41 PM
Yep fully warmed up. Throttle wide open battery charged. And yes I cranked a while on each cylinder. Fuel injection fuse and relay removed. What do you fellas think? I think it's time for a cylinder leakdown test. But i have never performed one before.
Do you have a leak down tester? Actually, it may be more useful to add a capful of oil into each cylinder through the spark plug hole(s) and perform a wet compression test. This will provide some information on your piston ring condition.

The readings, (140/115/123) if accurate, are on the low side, but not alarming on a well travelled Metro. The differences in compression readings between each cylinder are also concerning, as it indicates a +/- 20% variance, but in my opinion, this is a secondary concern that is not related to your 'too low'' cold idle speed symptoms. A properly adjusted throttle body,TPS and functional ISC should be able to produce a fast idle even on a worn engine during a cold start.

How does the engine perform overall? Does it accelerate smoothly? Do you notice any smoke from the exhaust or note any oil consumption? Have you had a chance to calculate your fuel mileage yet?



Tom i actually did a "wet" test by pouring oil into each cylinder prior to the compression test. And you know Tom it accelerates smoothly. I mean this is the first metro I have ever owned but it seems to accelerate and maintain speed with no problems. And yea you would think it would still maintain a decent idle even if it does have low compression. And hard to say if it uses oil or not because I just got it and haven't put many miles on it. But I don't notice any smoke out of the tailpipe which would indicate worn piston rings. And my last tank I averages 40.2 mpg half city miles and half highway miles on that tank.
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David95237


No sense in a leak down test. time for an overhaul.
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suzukitom
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Tom

It does sound like your car is running well.. since you already did the wet compression test, it would be good to see how much difference there is between those results and for a dry compression test. Do you have time to do that?

In the meantime, I'll prepare a few more closeup pictures of the throttle plate adjustment, which might help later.. the recent photobucket issue has caused a lot of technical pictures posted to GMF to become broken/lost.
Edited by suzukitom, Aug 16 2017, 09:53 PM.
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Dystopiate666
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Tree Banger

Is it getting pretty cold in Wisconsin already?

I would think it would still be starting with those compression numbers, my frame of reference on what actually constitutes a cold start are kind of skewed down here in Arizona, but my 98 started for a whole (AZ) winter with much lower compression.

As far as the rebuild, if you are happy with the performance, and its not burning too much oil for your comfort, I would say just keep driving it for the time being.

I agree with Tom, you should get some dry numbers to compare, your readings could be lower.
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Woodie
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David95237
Aug 16 2017, 09:49 PM
No sense in a leak down test. time for an overhaul.
:gp

If the test was done properly (and it sounds as if it was) and the compression gauge is working properly (you came here asking about all the symptoms of a worn out engine) then that engine is done. Time for a rebuild. With numbers that low, I suspect you'd better get it bored for bigger pistons.
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Bank2me
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Thanks guys for the input but wouldn't a leakdown test be beneficial to see if the head needs to be redone or if the bottom end does? Or would I be better off just getting the head redone and the lower end, in other words the whole works rebuilt? And thanks S uzukitom that sounds good I appreciate the help. I think the numbers on a dry test would just be lower though :(
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geo4thewin
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The way that I determine if I am just going to rebuild the head or if I need a full rebuild is to start with a dry compression test in each cylinder. Then I add a bit of oil to each and do the test over again. If the numbers don't go up, or only go up by a couple on the wet test then I only rebuild the head.

I understand that if you already have the motor apart you might as well get the bottom end rebuilt, but not everyone has the money for that. That is just my opinion though and I understand that not everyone agrees :P
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Bank2me
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Thanks geo4thewin. How much would a full rebuild/head redone cost on one of these engines?
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geo4thewin
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There are a million answers to that question, but I will take my best guess in order from least to most expensive

1. rebuild head yourself and replace gaskets with ebay gasket set and reused head bolts - $30 for gasket set + fluids
- remove head
- disassemble head
- clean carbon off of valves
- reassemble head
- clean carbon off the top of the pistons
- reinstall head with new gaskets

2. rebuild head yourself and replace gaskets with fel-pro gasket set and new head bolts - $100 for gasket set & head bolts + fluids
- same steps as option 1

3. rebuild head + rebuild bottom end yourself - $60+ depending on how cheap of parts you buy

4. take it to a shop and pick it up when it is ready - $300+

I would say it all depends on how much you want to spend and how long you want it to last. I have personally done option 1 twice and both of my cars are still running, one has been on the road for almost 2 years and about 8k miles and the other is about 4 months old and has about 3k miles on it. I don't know how long they will last, but to me it is worth the risk for $30 bucks :rocker
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Bank2me
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Dystopiate666
Aug 17 2017, 01:34 AM
Is it getting pretty cold in Wisconsin already?

I would think it would still be starting with those compression numbers, my frame of reference on what actually constitutes a cold start are kind of skewed down here in Arizona, but my 98 started for a whole (AZ) winter with much lower compression.

As far as the rebuild, if you are happy with the performance, and its not burning too much oil for your comfort, I would say just keep driving it for the time being.

I agree with Tom, you should get some dry numbers to compare, your readings could be lower.
Thanks and yea it's only got down to about 60-70 at night so not too cold but in winter time it gets cold here. It's a fun car to drive!! And I mean hell I bought it for the fuel mileage and I've always wanted to own one lol.
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Bank2me
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geo4thewin
Aug 17 2017, 11:53 AM
There are a million answers to that question, but I will take my best guess in order from least to most expensive

1. rebuild head yourself and replace gaskets with ebay gasket set and reused head bolts - $30 for gasket set + fluids
- remove head
- disassemble head
- clean carbon off of valves
- reassemble head
- clean carbon off the top of the pistons
- reinstall head with new gaskets

2. rebuild head yourself and replace gaskets with fel-pro gasket set and new head bolts - $100 for gasket set & head bolts + fluids
- same steps as option 1

3. rebuild head + rebuild bottom end yourself - $60+ depending on how cheap of parts you buy

4. take it to a shop and pick it up when it is ready - $300+

I would say it all depends on how much you want to spend and how long you want it to last. I have personally done option 1 twice and both of my cars are still running, one has been on the road for almost 2 years and about 8k miles and the other is about 4 months old and has about 3k miles on it. I don't know how long they will last, but to me it is worth the risk for $30 bucks :rocker
Oh really to rebuild it that's not bad to professionally get it done. I was thinking it would be like $2,000 to rebuild it professionally lll
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Dystopiate666
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Tree Banger

If you had the engine rebuilt and cut at a shop, I don't see getting out of it for that cheap.

It cost me 200 to have the block decked, cylinders bored and wrist pins pressed. Head work I got quoted about the same but decided to just lap in new valves myself.

My guess would be over 1000 for a real rebuild at a shop, including the machine work or head purchase.

If you are at all mechanically minded you can do a down and dirty rebuild yourself for almost nothing, but a new head is also cheap (reman for about 200$) and saves a lot of hassle and time.

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suzukitom
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Tom

I recently got a professional quote from a good machine shop to rebuild my project G16B 4 cylinder engine. It was $1600 labor plus parts with 18,000 mile warranty (Not including removal or installation.)

If it were my car, I would repeat the compression test with a known good gauge before breaking out my checkbook. You say it runs well and does not consume oil and the mileage is still pretty good. This doesn't quite match an engine needing an immediate rebuild in my opinion.

If you have someone to help do the compression test ask them to observe how the gauge needle rises. Eg. Does the needle jump incrementally higher with each revolution until it tapers off to a peak reading? (On my car, the peak value required about 8 revolutions to get to 190 psi.)
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Dystopiate666
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Tree Banger

:gp

There is a quantified spec for engine compression. Around 155psi per cylinder.

However....

If the mpg's are good, the oil consumption is minimal and performance is tolerable TO YOU, like I said before....keep driving it.

Eventually one of those exhaust valves will chip apart and you'll have a dead hole.

Of course, if the damn thing wont start due to low compression, guess that pretty much ends the debate.
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