Bad, bad, bad, news

85silverna · 12-17-2008, 03:58 PM

well did a compression test on my mr2... and didnt even have to go past the first cylinder, Only 55 lbs of compression. I guess that explains the miss I was experiancing. Anyway im pulling the valve covers off when I get the chance but Im afraid its probably the piston ring...

So I'm looking for advice and maybe a pity discount on an engine someone has laying around. I need to decide if I should pay another 800 to 900 bucks for a 4agze or a 20 valve, or if I should just look for another stock 4age. I already know I'll probably have to spend an obnoxious amount of cash either way between the new clutch, flywheel, engine, fuel pump, starter, and god knows what else... Anyway unless the head has a valve stuck partly open im looking at a rebuild or a swap, or worse... a partout

Papo J · 12-17-2008, 04:21 PM

Did you hold the throttle wide open while doing the test?

85silverna · 12-17-2008, 04:34 PM

I didnt do the test. but the shop that I took it to stopped at no. 1

so as soon as im done being pissed im going to borrow my friends comp tester and do it myself. I wanted the shop to do timing on the car because I do not have an old fashioned light. If I knew that they were just going to do a comp test and stop at the first cylinder I would have done it myself in the first place.

Its weird how the car behaves, one minute the car is bogged and drives like crap, (example: the mechanic pulling into traffic and almost getting rear-ended due to the lack of power) and the next the cars power is almost restored (like when I did a burnout with it leaving the shop) id assume the cat is acting up due to excess fuel. I don't think its a valve because theres no noise from it, it just sounds like its running with no spark in one cylinder. (im not stupid it has plenty of spark)

Papo J · 12-17-2008, 05:49 PM

From what I know, if you have bad compression it is not going to fix itself and it won't be intermittent. If it's low it will stay low. It sounds like you have either bad ignition wires or a vacuum leak before the AFM. Does the check engine light come on when it misses and bogges down like that?

tjmr2 · 12-18-2008, 12:09 AM

I'd be su****ious of a vacuum leak too, replacing all the vacuum hoses is a real cheap place to start. A compression test is a good tool, but to really diagnose a sad engine you need to do a leak down test. Follow this link for instructions on how to build and use one. They are cheap to build, and considering the cost of the project well worth the time to make and will tell you for certain if you have ring or valve problems, and where.

Which is pretty cool for a tool that costs less than $30 to make.

Building and Using a Cylinder Leakdown Tester

Good luck, keep us posted!

Gairloch · 12-18-2008, 12:28 AM

Quote:

Originally Posted by Papo J

From what I know, if you have bad compression it is not going to fix itself and it won't be intermittent. If it's low it will stay low. It sounds like you have either bad ignition wires or a vacuum leak before the AFM. Does the check engine light come on when it misses and bogges down like that?

Actually low compression can be intermittent. If it's a gap in the cylinder rings rather than something related to the valves it's possible that oil is filling the gap and allowing good enough compression for it to run reasonably well.

That being said, I'm with tjmr2 in suggesting that you consider doing a leakdown test.

If you don't want to bother with making your own tester EMSPowered has 'em too. Intake Leak Tester Intake Leak Tester [] - $44.99 : EMSPowered, High Quality, Great Service, Low Prices

85silverna · 12-18-2008, 02:52 AM

no check lights...and it doesn't regain full power, just some, enough to peel out but not to smoke them tires.

i guess ill go get a leakdown tester and see if the mech messed up, (and he might have, the boss is great but I don't like the guy who did the test.

Ive been through the vacuum lines a hundred times but this really sounds like a miss on only one cylinder.

dposer · 12-24-2008, 04:07 PM

check your valve lash, ignition timing, cam timing and look for loose wires around your senors and injectors

baktasht · 01-02-2009, 08:18 PM

could be a slipped timing belt as well.

85silverna · 01-06-2009, 05:14 AM

it might be... we just put it on

85silverna · 01-13-2009, 09:37 PM

well I finally did my own compression test on each cylinder, and the lowest value was 110 and the highest was 155. Don't worry I have already alerted the shop owner that his mechanic is an idiot. Anyway looks like its running lean... really really lean, and whaddya-Know? coolant temp sensor is shot, egr is stuck open and the fuel injectors are barely getting current. I'm starting with the coolant sensor and working my way to the injectors (bad ground maybe?). Anyway until this motor is shot, I'm going to flogg it as much as possible. then a 20v blacktop is in order

HoLun · 01-31-2009, 01:25 AM

more like they try to upsell you an engine, who does compression test on only 1 cylinder?

Jackstand Queen · 01-31-2009, 02:59 PM

110 PSI is way into the unacceptable zone. Enough to make the engine run like Butt.

Rather than rebuilding, I think you are on the best track of just getting a used JDM.

Doing a swap to 20v would require exhaust mods, wiring harness mods, different ECU, ignitor, and some small re-routing of coolant hoses.

Doing a 4agze swap would entail the same issues. Plus if you went with a heavy matching SC tranny, redoing the axles, suspension springs, tranny mounts. I almost forgot about obtaining an SC relay, and an IC regulator, and intercooler, TB, and Misc. intake tubing.

So you'd need a lot more money and time (and patience) to do a swap rather than find another 4age. I'd recommend the 4agze route myself. These cars are just underpowered unless SC'd or turbo'd. I owned an NA for over 6 years and was never happy with it. It was always too slow.

HoLun · 01-31-2009, 07:43 PM

before you jump the gun and start replacing engines, try to soak some ATF in the cylinders to see if its caused by stuck rings, ATF should help free stuck rings or use Auto RX.

the 30k JDM engine got so much carbon on the pistons, all the rings are semi stuck, the oil rings are completely stuck, i took them out and clean them off, now they are free like a new set of ring.

85silverna · 02-02-2009, 02:32 PM

110 isnt the cause of the problems i have now though. It doesnt sound like im getting fuel. I just did the filter, and the pump seems fine, the injectors are getting charge... im stumped... pressure regulator maybe? Im going to play with the timing later today...

Jackstand Queen · 02-02-2009, 02:45 PM

Corroded terminals on your twenty year plus old wiring harness could be the cause of running terribly. Unplug all connectors and check for corrosion, clean as necessary.

110 PSI would definitely keep the engine from peak performance. But it wouldn't explain chugging down the road at top speed of 25 MPH.

I gotta agree with Holun on jumping the gun with engine replacement. On a really old engine that has been ill maintained and not driven for years, gummed up rings could be cleaned up with solvents and some driving.

85silverna · 02-03-2009, 03:06 PM

any good solvents to use? and put them where? in the ignition chamber? hey it wont start right now, hell if I start putting crap in there it'll never start

HoLun · 02-03-2009, 04:58 PM

put some atf in the cylinder thru the sparkplug holes,, leave the plugs out, rotate the engine by hand, then let it sit overnight, but you should do a leak down test to see what is not sealing first.

Jackstand Queen · 02-03-2009, 08:30 PM

Seafoam is a product I've heard of but never used. But it is very severe. A badly running engine could end up running worse after using this stuff.

If it were my car, I'd use a full can of Berryman's carburator cleaner. Its pure paint thinner: toluene. At the same time, I'd add 2 or 3 OZ of synthetic chain saw oil. To counter the toluene's tendency to wash away the engine oil.

And yes a fuel pressure regulator gone bad could cause the car to run like Butt. Grab an ear washer squeeze bulb from the drug store. Now squeeze the bulb and plug into the vacuum line that goes to the fuel pressure regulator. The engine should burble, and respond with slight RPM gain (100+ RPM) while idling. If there is nill response, you need to buy a FPR. FPR's made by aftermarket companies seem to work well. No need to pay three times as much at the Yota dealer. (standing by for flames on this opinion).

I read this entire post again. Engine won't start? Pull a plug wire, stick something metal up in the boot. Hold object 1.5" above the valve covers. Have someone crank the motor over. Should be getting a nice blue spark. Orange is not as good. Red spark at closer range is bad.

After you attempt to start the engine, immediately pull out a spark plug. It should be slightly damp with gasoline. It should at least smell strongly of gasoline.

You might buy, order online, or at the local parts store a copy of Hanes mr2 repair manual 84 to 87. Either that or find the free download of the BGB, big green book online. Its over a 1000 pages long, and more difficult to use, yet much more intimidating.

85silverna · 02-18-2009, 01:09 AM

well the weather cleared today and I spent an hour with my 2. I tried to get it started... I really did... anyway after I got frustrated that it wouldn't run longer than 30 seconds, I pulled the dizzy... and its shot. the copper coil under the rotor was shredded, its a wonder the car ran at all.

12-17-2008, 03:58 PM	#1 (permalink)
85silverna Some Skills Join Date: Nov 2008 Posts: 85 Thanks: 1 Thanked 1 Time in 1 Post iTrader Rating: (3/100% )	Bad, bad, bad, news well did a compression test on my mr2... and didnt even have to go past the first cylinder, Only 55 lbs of compression. I guess that explains the miss I was experiancing. Anyway im pulling the valve covers off when I get the chance but Im afraid its probably the piston ring... So I'm looking for advice and maybe a pity discount on an engine someone has laying around. I need to decide if I should pay another 800 to 900 bucks for a 4agze or a 20 valve, or if I should just look for another stock 4age. I already know I'll probably have to spend an obnoxious amount of cash either way between the new clutch, flywheel, engine, fuel pump, starter, and god knows what else... Anyway unless the head has a valve stuck partly open im looking at a rebuild or a swap, or worse... a partout

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12-17-2008, 04:21 PM	#2 (permalink)
Papo J 6SPD GTE Join Date: Sep 2006 Posts: 189 Thanks: 1 Thanked 19 Times in 18 Posts iTrader Rating: (0/0% )	Did you hold the throttle wide open while doing the test?

12-17-2008, 04:34 PM	#3 (permalink)
85silverna Some Skills Join Date: Nov 2008 Posts: 85 Thanks: 1 Thanked 1 Time in 1 Post iTrader Rating: (3/100% )	I didnt do the test. but the shop that I took it to stopped at no. 1 so as soon as im done being pissed im going to borrow my friends comp tester and do it myself. I wanted the shop to do timing on the car because I do not have an old fashioned light. If I knew that they were just going to do a comp test and stop at the first cylinder I would have done it myself in the first place. Its weird how the car behaves, one minute the car is bogged and drives like crap, (example: the mechanic pulling into traffic and almost getting rear-ended due to the lack of power) and the next the cars power is almost restored (like when I did a burnout with it leaving the shop) id assume the cat is acting up due to excess fuel. I don't think its a valve because theres no noise from it, it just sounds like its running with no spark in one cylinder. (im not stupid it has plenty of spark)

12-17-2008, 05:49 PM	#4 (permalink)
Papo J 6SPD GTE Join Date: Sep 2006 Posts: 189 Thanks: 1 Thanked 19 Times in 18 Posts iTrader Rating: (0/0% )	From what I know, if you have bad compression it is not going to fix itself and it won't be intermittent. If it's low it will stay low. It sounds like you have either bad ignition wires or a vacuum leak before the AFM. Does the check engine light come on when it misses and bogges down like that?

12-18-2008, 12:09 AM	#5 (permalink)
tjmr2 Cage Fighter Join Date: Jan 2008 Location: Colorado Posts: 310 Thanks: 0 Thanked 49 Times in 46 Posts My Google Map iTrader Rating: (0/0% )	I'd be su****ious of a vacuum leak too, replacing all the vacuum hoses is a real cheap place to start. A compression test is a good tool, but to really diagnose a sad engine you need to do a leak down test. Follow this link for instructions on how to build and use one. They are cheap to build, and considering the cost of the project well worth the time to make and will tell you for certain if you have ring or valve problems, and where. Which is pretty cool for a tool that costs less than $30 to make. Building and Using a Cylinder Leakdown Tester Good luck, keep us posted!

12-18-2008, 02:52 AM	#7 (permalink)
85silverna Some Skills Join Date: Nov 2008 Posts: 85 Thanks: 1 Thanked 1 Time in 1 Post iTrader Rating: (3/100% )	no check lights...and it doesn't regain full power, just some, enough to peel out but not to smoke them tires. i guess ill go get a leakdown tester and see if the mech messed up, (and he might have, the boss is great but I don't like the guy who did the test. Ive been through the vacuum lines a hundred times but this really sounds like a miss on only one cylinder.

12-24-2008, 04:07 PM	#8 (permalink)
dposer No Skills Join Date: Dec 2008 Posts: 5 Thanks: 0 Thanked 0 Times in 0 Posts iTrader Rating: (0/0% )	check your valve lash, ignition timing, cam timing and look for loose wires around your senors and injectors

01-02-2009, 08:18 PM	#9 (permalink)
baktasht EMSPowered.com Join Date: Oct 2005 Location: Austin, TX Posts: 4,672 Thanks: 19 Thanked 133 Times in 118 Posts My Google Map iTrader Rating: (41/98% )	could be a slipped timing belt as well.

01-06-2009, 05:14 AM	#10 (permalink)
85silverna Some Skills Join Date: Nov 2008 Posts: 85 Thanks: 1 Thanked 1 Time in 1 Post iTrader Rating: (3/100% )	it might be... we just put it on

01-13-2009, 09:37 PM	#11 (permalink)
85silverna Some Skills Join Date: Nov 2008 Posts: 85 Thanks: 1 Thanked 1 Time in 1 Post iTrader Rating: (3/100% )	well I finally did my own compression test on each cylinder, and the lowest value was 110 and the highest was 155. Don't worry I have already alerted the shop owner that his mechanic is an idiot. Anyway looks like its running lean... really really lean, and whaddya-Know? coolant temp sensor is shot, egr is stuck open and the fuel injectors are barely getting current. I'm starting with the coolant sensor and working my way to the injectors (bad ground maybe?). Anyway until this motor is shot, I'm going to flogg it as much as possible. then a 20v blacktop is in order

01-31-2009, 01:25 AM	#12 (permalink)
HoLun ASE Master tech Join Date: Jan 2009 Location: Austin, TX Posts: 79 Thanks: 0 Thanked 5 Times in 5 Posts iTrader Rating: (0/0% )	more like they try to upsell you an engine, who does compression test on only 1 cylinder?

01-31-2009, 02:59 PM	#13 (permalink)
Jackstand Queen Cage Fighter Join Date: May 2008 Posts: 677 Thanks: 52 Thanked 56 Times in 53 Posts iTrader Rating: (1/100% )	110 PSI is way into the unacceptable zone. Enough to make the engine run like Butt. Rather than rebuilding, I think you are on the best track of just getting a used JDM. Doing a swap to 20v would require exhaust mods, wiring harness mods, different ECU, ignitor, and some small re-routing of coolant hoses. Doing a 4agze swap would entail the same issues. Plus if you went with a heavy matching SC tranny, redoing the axles, suspension springs, tranny mounts. I almost forgot about obtaining an SC relay, and an IC regulator, and intercooler, TB, and Misc. intake tubing. So you'd need a lot more money and time (and patience) to do a swap rather than find another 4age. I'd recommend the 4agze route myself. These cars are just underpowered unless SC'd or turbo'd. I owned an NA for over 6 years and was never happy with it. It was always too slow.

01-31-2009, 07:43 PM	#14 (permalink)
HoLun ASE Master tech Join Date: Jan 2009 Location: Austin, TX Posts: 79 Thanks: 0 Thanked 5 Times in 5 Posts iTrader Rating: (0/0% )	before you jump the gun and start replacing engines, try to soak some ATF in the cylinders to see if its caused by stuck rings, ATF should help free stuck rings or use Auto RX. the 30k JDM engine got so much carbon on the pistons, all the rings are semi stuck, the oil rings are completely stuck, i took them out and clean them off, now they are free like a new set of ring.

02-02-2009, 02:32 PM	#15 (permalink)
85silverna Some Skills Join Date: Nov 2008 Posts: 85 Thanks: 1 Thanked 1 Time in 1 Post iTrader Rating: (3/100% )	110 isnt the cause of the problems i have now though. It doesnt sound like im getting fuel. I just did the filter, and the pump seems fine, the injectors are getting charge... im stumped... pressure regulator maybe? Im going to play with the timing later today...

02-02-2009, 02:45 PM	#16 (permalink)
Jackstand Queen Cage Fighter Join Date: May 2008 Posts: 677 Thanks: 52 Thanked 56 Times in 53 Posts iTrader Rating: (1/100% )	Corroded terminals on your twenty year plus old wiring harness could be the cause of running terribly. Unplug all connectors and check for corrosion, clean as necessary. 110 PSI would definitely keep the engine from peak performance. But it wouldn't explain chugging down the road at top speed of 25 MPH. I gotta agree with Holun on jumping the gun with engine replacement. On a really old engine that has been ill maintained and not driven for years, gummed up rings could be cleaned up with solvents and some driving.

02-03-2009, 03:06 PM	#17 (permalink)
85silverna Some Skills Join Date: Nov 2008 Posts: 85 Thanks: 1 Thanked 1 Time in 1 Post iTrader Rating: (3/100% )	any good solvents to use? and put them where? in the ignition chamber? hey it wont start right now, hell if I start putting crap in there it'll never start

02-03-2009, 04:58 PM	#18 (permalink)
HoLun ASE Master tech Join Date: Jan 2009 Location: Austin, TX Posts: 79 Thanks: 0 Thanked 5 Times in 5 Posts iTrader Rating: (0/0% )	put some atf in the cylinder thru the sparkplug holes,, leave the plugs out, rotate the engine by hand, then let it sit overnight, but you should do a leak down test to see what is not sealing first.

02-03-2009, 08:30 PM	#19 (permalink)
Jackstand Queen Cage Fighter Join Date: May 2008 Posts: 677 Thanks: 52 Thanked 56 Times in 53 Posts iTrader Rating: (1/100% )	Seafoam is a product I've heard of but never used. But it is very severe. A badly running engine could end up running worse after using this stuff. If it were my car, I'd use a full can of Berryman's carburator cleaner. Its pure paint thinner: toluene. At the same time, I'd add 2 or 3 OZ of synthetic chain saw oil. To counter the toluene's tendency to wash away the engine oil. And yes a fuel pressure regulator gone bad could cause the car to run like Butt. Grab an ear washer squeeze bulb from the drug store. Now squeeze the bulb and plug into the vacuum line that goes to the fuel pressure regulator. The engine should burble, and respond with slight RPM gain (100+ RPM) while idling. If there is nill response, you need to buy a FPR. FPR's made by aftermarket companies seem to work well. No need to pay three times as much at the Yota dealer. (standing by for flames on this opinion). I read this entire post again. Engine won't start? Pull a plug wire, stick something metal up in the boot. Hold object 1.5" above the valve covers. Have someone crank the motor over. Should be getting a nice blue spark. Orange is not as good. Red spark at closer range is bad. After you attempt to start the engine, immediately pull out a spark plug. It should be slightly damp with gasoline. It should at least smell strongly of gasoline. You might buy, order online, or at the local parts store a copy of Hanes mr2 repair manual 84 to 87. Either that or find the free download of the BGB, big green book online. Its over a 1000 pages long, and more difficult to use, yet much more intimidating.

02-18-2009, 01:09 AM	#20 (permalink)
85silverna Some Skills Join Date: Nov 2008 Posts: 85 Thanks: 1 Thanked 1 Time in 1 Post iTrader Rating: (3/100% )	well the weather cleared today and I spent an hour with my 2. I tried to get it started... I really did... anyway after I got frustrated that it wouldn't run longer than 30 seconds, I pulled the dizzy... and its shot. the copper coil under the rotor was shredded, its a wonder the car ran at all.