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Running Hella Rich

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93RS

10+ Year Contributor
140
2
Oct 3, 2011
Brandon, South_Dakota
My Laser is running super super rich and im not sure why.... another concern is that my stock boost guage is way far off... ie my aftermarket will read -10vac and my stock one will be reading 7-10lbs of boost... When I go WOT the stock guage instantly shoots to 14. I am well aware the stock guage is just a guess but why would it be 7 to 14lbs off??? What happens to these cars when the MAF goes out??? How about a FPR??? Since its been cold out here in South Dakota its been running better, but it used to act like it was hitting fuel cut... Its NOT a boost leak, thats about the only thing I can tell you for sure. Just really at a loss and would like to get it running properly b4 snow falls here. Any and all help is greatly appreciated!:laser:
 
How's the ECU? T-stat okey, or stuck open keeping the system cool where the Temp Sensor is telling the ECU to dump in more fuel to get the block heated up where it's programmed to be at to get the system back into a closed loop condition?

You using a 195 degree T-stat or colder-which would keep things on the rich side as well if not the 195 degree range..
 
I just changed the cts and the tstat is working to the best of my knowledge.... I havent checked the ecu but I dont smell any fish and my CEL comes on for 3-5 secs then turns off at startup... so I would assume that isnt it... Im just at a complete loss... Last time I had the intake out the MAF didnt look the cleanest but everyone says not to clean em because theyre Karmen Vortex sensors and there is no safe cleaner...
 
injectors dirty? bad spray pattern could cause issue but you would lose power and should get an engine light
 
Bad MAF or front o2 could be the cause. Could also be boost/vacuum leak. If MAF is dirty I would definitely clean it first. You can clean it with electrical parts cleaner for wire connectors and such. Such as CRC electronics cleaner at autozone or whatever parts store. And do a boost leak test also.
 
1G's only have one o2 sensor mounted in the EXH manifold, but true it could be lazy enough to not do the work and not throw a CEL

both of the DSM's I've owned were and are 2g's so thats good to know. But I did have a problem with one of them running rich that an o2 senser seemed to have fixed.
 
So clean the MAF... Its NOT a boost leak done about 5 BLTs, as far as the o2 I've never heard of a dead one not throwing codes...

Yes, you can clean it with electronics cleaner. I can say from experience that an o2 sensor can die and not throw a code. Actually mine died and got a code for coolant temp sensor WTF. I'm willing to bet the problem is in the MAF, since the stock boost gauge "guesses" based on the MAF. Higher reading means more air being registered, which means more fuel added.
How is your idle? Do you have a logger?
 
Probably slim, it's more than likely the o2. Mine was garbage and I was getting 12-15mpg's when I first bought my car and and it never threw a light, changed it out and was back to 20-23mpg in the city and about 28 highway.
 
My boost gauge is hooked hooked up to one of the lines going to the FPR... I should have my oxygen sensor either tomorrow or thursday. Any idea what size socket the oxygen sensor is??? I know I need a special socket just curious with what size it is.
 
My boost gauge is hooked hooked up to one of the lines going to the FPR... I should have my oxygen sensor either tomorrow or thursday. Any idea what size socket the oxygen sensor is??? I know I need a special socket just curious with what size it is.

As long as it's the line connected to the manifold, that's good. O2 sensor should be 7/8"
 
Just got the new O2 in and it didn't seem to help.. I'm gonna put plugs in it later today and pull the computer out and check the caps in that.... I'm hoping the computer is the culprit I'm tired of just dumping money into it and getting no results.... If anyone has any other ideas here is some info.... It has 215k miles so far I have changed the CTS, 2 sets of plugs and wires. When it'd idling it is very sporadic sometimes it idles at 15k and surges other times it's about 8k and struggling.... It runs a million times better when it's below 50 degrees outside and it runs like shit when it's nice outside.... It starts breaking up around 33k and gets ovet it around 43k.... Almost 100% positive it's not a boost leak... Only mods are a 2g TB elbow, hard pipes, and a MBC...
 
Yep, or you can have it already idling and then unplug it. If the MAF is bad the idle will stabilize but closer to 1200-1500rpms, you'll be hard pressed to get it to rev decent though since the computer has no idea how much fuel to inject.
 
+ 1 on the maf. i switched to speed density when mine went out, never looked back. the reason it runs good when its cold out is because the ecu is throwing fuel at the engine to help protect it from going lean. i bet if you start it at 25* it wil idle good. the colder it is the more fuel the engine will need, so thats why it runs better at colder temps.
 
Unplugged the MAF the idle stayed the same until I plugged it back in then it went normal for a couple of seconds.... Assuming that means it ain't the MAF so I'll try to get the computer pulled later today.... Should the battery be disconnected to pull the computer?
 
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