Overheating and No Power

[maytimaws]

Hi,

I have a 1993 Mazda 626.

1st Problem - Overheating after 2 hours or around 100kms run. I understand I have to check the radiator and the whole cooling system. I will have it done right away.

2nd Problem - When my temperature is already high (without overheating yet), I loses power. Meaning, gumagaralgal na yung makina ng kotse at ayaw nang mag-move kahit buhay pa yung makina. Hindi din tumataas ang RPM and yung idling ko ay sobrang baba - around .5 RPM.

What I need to do, especially when I am caught in traffic - is to shut down the engine, re-start and make some revolutions para tumaas ulit ang RPM. This will do for another 30-50kms.

When I can make it on first instance and whenever I can possibly park, lalagyan ko lang ulit ng tubig ang radiator dahil laging kokonti na lang ang natira.

Here's my question: Aside from the radiator, do the following parts has connection to this problem?

1. MAF/Air Flow Sensor
2. Water Pump (Which I think should also be checked if I need to run through the whole cooling system)
3. Cylinder Head/Gasket
4. Fuel Pump

2nd question - if I need to have all these checked, which one should go first? 2nd? 3rd and etc?

TIA!

[oj88]

When the loss of power happens just before the gauge shows it's overheating, I think it could be either:

1. The pistons may be starting to seize up
2. The ECU is limiting power (limp mode) to preserve the engine

Things to check:

1. Cooling system - Check the coolant level, radiator fans, water pump, thermostat
2. Engine - Check the oil level, condition and pressure (Yes, engine oil also works to cool the engine)

Is the Check Engine Light (CEL) on?

[maytimaws]

When the loss of power happens just before the gauge shows it's overheating, I think it could be either:

1. The pistons may be starting to seize up
2. The ECU is limiting power (limp mode) to preserve the engine

Things to check:

1. Cooling system - Check the coolant level, radiator fans, water pump, thermostat
2. Engine - Check the oil level, condition and pressure (Yes, engine oil also works to cool the engine)

Is the Check Engine Light (CEL) on?

Sir oj88,

CEL is off.

1. What do you mean by "piston is seizing up"? Do I need to have it re-calibrated?
2. I know how to check the oil level, but how can I check the Oil pressure? May gauge po ba dito?

Thank you for the above information!

[shok]

Piston seizes because metal expands when heated. If the engine is already above operating temp the expansion of the piston rings causes the engine to seize or hesitant to rev dahil sumisikip na sya at mataas na ang friction.

Kung nauubusan ng tubig have your cooling system checked for leaks. Items to check are the radiator, rad cap, hoses, hose fittings, thermostat and water pump. Normally may bakas ng watermarks kung san may tagas o tulo. Kung walang tulong makita, it could be a leaking cylinder head gasket. Check your oil kung may water na humahalo. Kung meron head gasket ang prublema.

[1D4LV]

overheating tapos loss of power.... typical reason why a car losses power with history of overheating is due to engine issues.... tama baka may piston issues.

siguro mas maganda kung ma-diagnose ng maayos. baka kailangan na i-overhaul din yan.

[maytimaws]

Piston seizes because metal expands when heated. If the engine is already above operating temp the expansion of the piston rings causes the engine to seize or hesitant to rev dahil sumisikip na sya at mataas na ang friction.

Kung nauubusan ng tubig have your cooling system checked for leaks. Items to check are the radiator, rad cap, hoses, hose fittings, thermostat and water pump. Normally may bakas ng watermarks kung san may tagas o tulo. Kung walang tulong makita, it could be a leaking cylinder head gasket. Check your oil kung may water na humahalo. Kung meron head gasket ang prublema.

Thanks again Sir! First check, may leak sa hose, which I just saw kasi the water is running through papuntang mags kaya di agad nakita.

"If the engine is already above operating temp the expansion of the piston rings causes the engine to seize or hesitant to rev dahil sumisikip na sya at mataas na ang friction." - Looks like this is the case. Since I'm not experiencing it when the temp is still low.

Hopefully, this will be the ONLY case. Nonetheless, will also check the oil and cylinder head gasket. :cheer2:

[shok]

Correct the problem and observe mo muna.
Dapat hindi nababawasan ng coolant ang radiator. Yan ang cause ng overheating problem mo.
Kung nababawasan pa din, may iba pang source ng leak yan na kailangan hanapin.
Kung walang external leak, dun na sa cylinder head gasket ang inspection. Check oil kung may humahalong tubig. Tumataas ba ang level ng oil ng hindi naman dinadagdagan kasi nagkakaraoon na ng water content galing sa cooling system?

Top overhaul na solution dyan pag may leak sa cylinder head gasket. Sana wala naman at yun lang hose leak.

[shok]

Correct the problem and observe mo muna.
Dapat hindi nababawasan ng coolant ang radiator. Yan ang cause ng overheating problem mo.
Kung nababawasan pa din, may iba pang source ng leak yan na kailangan hanapin.
Kung walang external leak, dun na sa cylinder head gasket ang inspection. Check oil kung may humahalong tubig. Tumataas ba ang level ng oil ng hindi naman dinadagdagan? Nagkakaraoon na kasi ng water content galing sa cooling system kaya tumataas pag may leak ang cylider head gasket.

Top overhaul na solution dyan pag may leak sa cylinder head gasket. Sana wala naman at hose leak lang talaga.

[dr. d]

how's the oil pressure?

[maytimaws]

Correct the problem and observe mo muna.
Dapat hindi nababawasan ng coolant ang radiator. Yan ang cause ng overheating problem mo.
Kung nababawasan pa din, may iba pang source ng leak yan na kailangan hanapin.
Kung walang external leak, dun na sa cylinder head gasket ang inspection. Check oil kung may humahalong tubig. Tumataas ba ang level ng oil ng hindi naman dinadagdagan? Nagkakaraoon na kasi ng water content galing sa cooling system kaya tumataas pag may leak ang cylider head gasket.

Top overhaul na solution dyan pag may leak sa cylinder head gasket. Sana wala naman at hose leak lang talaga.

Here are the things I've done so far:

1. Radiator - I have it checked and lo, the elbow has two holes already. The radiator has 2 small leaks but the bulk of water loss is coming from the elbow. Repaired, while I'm waiting for my evercool radiator order. Effect: No overheating anymore; however, my coolant reservoir has leak so I have to find a replacement as well. For the meantime, walang coolant muna.

2. Fuel Pump and Fuel Filter - I brought the car to an electrician (Eddie Boy of Evangelista) to check the power loss. First resolution was to change the fuel pump. Car's engine is still running even at very low power. Easy starting pa din kaya eliminated na yung ignition coil. Pinalitan ko na din ang filter to be sure. During this time, I changed the CV Joint na din (Golden Isuzu) but I doubt if this have any effect on the issue. Effect: Power is back.

New problem - Low idling (500) and very strong vibrations even at a high RPM of 3,000. Hindi talaga nawawala yung vibration at any RPM level - then namamatay na ang makina kapag naka-on ang A/C.

3. Spark Plugs - The electrician advised to have the spark plugs replaced and I did. The number 2 is busted (sunog) na. I still replaced all. However nothing changed. Worse, the engine would start then eventually will die.

4. Checked Alternator - registered at an average of 13volts.

5. MAF - The MAF hose is already cut and it was remedied by using aluminum foil tape and another layer of electrical tape since we can't find any replacement yet. - Engine wouldn't die anymore but the original problem is still there - low idling and vibrations.

The electrician's last resort is to have a piston compression test.

Any thoughts? TIA!

[maytimaws]

how's the oil pressure?

How can I check it? Can it be done DIY? If so, what should be the acceptable readings?

[niky]

Best check the cam position sensor inside the distributor, also.

[maytimaws]

Best check the cam position sensor inside the distributor, also.

Noted Sir.

I checked on Youtube how to do it and it looks very tedious, so no DIY for me, right?

[niky]

Noted Sir.

I checked on Youtube how to do it and it looks very tedious, so no DIY for me, right?

Pretty much.

Had a 626 before... after it suffered overheating issues, the CPS went. Pain the ass to fix, and expensive, too. Ten years ago, the part was 30k, because it was built into the distributor cap... unlike newer CPS units which are standalone and cost in the 3-5k range.

[shok]

Reminds me of the first gen lynx...

Niky is right. Check CPS first. The coil or the connections inside might have been damaged due to the frequent overheating before. Your power loss symptom when engine is above normal operating temp/right before overheating may already be a sign of intermittent malfunction of the CPS.

Good luck!

[maytimaws]

Thanks Sirs Nicky and Shok for the inputs.

I read somewhere to do a brake-pump reset.

I pumped brake around 20 times and the vibration was gone! Anyone can tell me the logic behind this?

Nonetheless, I'll still do the cps check and throttle and mad cleaning to be sure.

[maytimaws]

Maf cleaning

[Ran Dz]

i think sa piston ang problema...madami sa evabgelista who specialize sa piston..kse almost everything na check naor sa coil mismo..medyo mabigat za bulsa lang