Extremely Hot Engine

[MEz]

STORY: Over the weekend driving to Phoenix (36 miles) I push on the gas to pass an 18 wheeler which took about 3 full seconds until the first glimpse of power decided to show. I get to my destination and park to a high surging idle (1.5-2k) and an extremely hot engine bay, The intake manifold was just as hot as the exhaust manifold.

REPAIR: Decided to remove the Manual Boost controller and I ran a boost leak test and found that one of my injector seals was completely torn. I sealed up the leaks to find that the problem didn't go away, the only difference was the the surge lowered only slightly but the engine still remains hot.

REPAIR 2: Today I swapped out the o2 sensor with a spare that I have resulting in a 1k-1.2k idle surge with a narrowband that cant stay still between rich and lean and with the engine still hot.

I know that its a sensor, problem is which one?

 

[92AWDHX40]

Terry's Talon Troubleshooting Tips #3 - Fast Idle (aka. Idle Surge)


start here not sure what you want the narrow band to do.

 

[Gasolinebaptism]

You say you have a hot bay, what did the temp gauge show? I'm assuming you don't have link or a logger that was running, nor an aftermarket temp gauge.
And it's not weird for an intake manifold on a turbo car to get hot, especially if you've upped boost and have heatsoaked your IC. Then the already high bay temps from a high performance motor, and exhaust manifold, turbo and o2 sensor housing that probably no longer have heat shields..
Sure, your bay will get hot, you need to cut boost to lower intake temps unless you have an efficient IC.

 

[jeber21]

yeah^ it actually sounds like you have a crappy ic system and if not try replcing your sensors

 

[MEz]

You say you have a hot bay, what did the temp gauge show? I'm assuming you don't have link or a logger that was running, nor an aftermarket temp gauge.
And it's not weird for an intake manifold on a turbo car to get hot, especially if you've upped boost and have heatsoaked your IC. Then the already high bay temps from a high performance motor, and exhaust manifold, turbo and o2 sensor housing that probably no longer have heat shields..
Sure, your bay will get hot, you need to cut boost to lower intake temps unless you have an efficient IC.

I Don't have any aftermarket temp. gauges but the stock water temp is fine. My main concern is that it get extremely hot (almost as hot as the exhaust manifold) when driven only commute 5 miles.

 

[007jimmy]

Are your heat shields in place?

 

[MEz]

Haven't had the heat shields in place yet and have have had the same IC set-up for about a year and never got this hot, but that wouldn't explain the idle surge. I suspect the MAP sensor.

 

[007jimmy]

Its not a map sensor. Its an MDP sensor and its for EGR purposes. If you have idle surge you have a leak at or after the throttle body. Air is bypassing your throttle plate and causing the surge. I would do a boost leak test. These engines are always hot. I would try to source some heat shields and you would be surprised at the difference. I put mine back on for this reason.

 

[Gasolinebaptism]

If your intake manifold is getting that hot, then your intake gasses are hotter than they should be. Simple as that.. You can try cleaning your OEM IC core, it may help. I've seen the fins completely packed tight with dirt.

 

[MEz]

After reading some more into the issue it seems to be that its normal for this extreme heat in the engine bay during the summer, but man the bay is so hot that I can feel it through the firewall and its suspicious that one day it was fine and the next its hot. Also found on the Silvia forums that it could also be the the thermostat. I know the oems open around 175 give or take a few degrees.

 

[AngelOfPassion]

Mine is doing the same thing, I can feel it on my feet when I drive. I am going to get some of my exhaust ceramic coated to try to fight it. I don't have the surge though...

 

[jtmcinder]

A phenolic spacer plus water injection solved this issue for me. Never had the hot-start-(won't-start) issue again, either.

 

[PieEyedPiper]

While reading this all I could say to myself was normal, normal, normal, well then replace it, normal normal...
If you still think you're running too hot, but not hot enough to trigger your stock temp gauge, then do some easy things first like fixing all boost leaks, replacing heatshields and changing your coolant could help.

Oh, and leave your 02 sensor alone.

A phenolic spacer plus water injection solved this issue for me. Never had the hot-start-(won't-start) issue again, either.

Those things have been on my list for ages.. and really makes me wonder about a discussion I had with Darren recently regarding the hot start since a major topic was pooling of fuel that is accounted for in the ECU but can evaporate when the car is shut off hot.

 

[jtmcinder]

I know that you know this, but I'm going to say it anyway...

A spacer and water injection will not solve the problems caused by leaky injectors. In fact, adding water injection adds one more thing that can leak - viz, the water-injection solenoid.

With that said, it would not surprise me one bit if hot intake-manifolds and fuel-rails contribute to the early onset of leaky injectors. Therefore, it would not surprise me if adding the spacer and water-injection, and having your injectors cleaned at the same time, created the most reliable and long-lived system.

 

[MEz]

What function does the MAP/MDP sensor run?

 

[PieEyedPiper]

MDP sensor, Do you really need this? - DSM Forums: Mitsubishi Eclipse, Plymouth Laser, and Eagle Talon Forum: DSMtalk.com
http://www.dsmtuners.com/forums/maintenance-repairs/398815-p1400-mdp-sensor.html
http://www.dsmtuners.com/forums/newbie-forum/281724-do-i-need-mdp-map-sensor.html

RRE's Eclipse 2g Turbo to 1g Head Swap Tips

Here is some information about the MDP sensor. I'm sure there is much more available.

Unless you have a CEL, I'd maybe start pulling apart the throttlebody/EGR/FIAV just to make sure everything is the way it's supposed to be. Probably wouldn't hurt to ohm out your isc while you're at it, but this doesn't really sound too much like isc idle fluctuations.

Have you been through this? http://www.dsmtuners.com/forums/articles-engine-fuel/191137-how-fix-your-idle-surge-problem.html
Try this one, too. http://www.dsm.org/how-tos/tttt/tttt3.html

 

[99boostedgst]

I am idleing at about 1800-2300 right now so I have this problem to, but when I turn the car off it stays running for a good couple secs then shuts off and also I'm haven the really really hot motor, even the VC is hella hot/no I don't have any sheilds or any wraps extra, any help is nice

Thanks
Dustin.

Ect. Not extra

 

[PieEyedPiper]

any help is nice

Put your heat shields back on, or start wrapping. Otherwise the above links should be pretty much all you need. If not, you can always start your own thread.