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1G stutter 75% of the time in/out of boost

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93AWDDSM

10+ Year Contributor
883
40
Jan 1, 2009
Vancouver, Washington
So, I have this extremely annoying problem. The car struggles to accelerate most of the time. It will build full boost (14lbs) but have no power and I can feel the hesitation. When cruising and not in boost with the gauge around -10 in Hg I can feel it like hesitate and right then if I WOT it goes directly into boost but again lack of power but sometimes if I let off once or twice it will pull normal-ish. Could my o2 sensor be toast, if so I'll be replacing it shortly, also the car gets extremely bad mpg. I'm talking like 9-12 mpg without boost :(

I've replaced:
coil pack
spark plug and wires
pcv valve
**checked for Boost leaks
 
It seems wierd to me tho that it wouldnt throw a cel by having the O2 completely disconnected. Im sure even the computers of that time would be able to say "hey my o2 sensor is gone better let the boss know" and if there was something wrong with the circuit it should still throw a fault code
 
nope no obd 2 port for us. I'll try the multi meter here shortly and see what I get. The thing is, even when I unplugged the sensor, it's like the ecu didn't even notice as in no CEL. So was my o2 not reporting to ecu for who knows how long?

If I remember correctely, When my o2 died, i got no cel on my 1g.
But i have an o2 gauge and data logger, so I saw that my car was running way to rich.
I give you the ecu pin out for 1g

http://www.zeitronix.com/Products/O2Meter/O2Meter.shtml
Or
http://projectzerog.com/wiring_info.shtml

Save the dsm:thumb:
 
I am going to be picking up exhaust gaskets this weekend and repairing a broken exhaust stud and try to get some new crush washers for my good old 14b Hopefully that helps. After completion of that, I was thinking maybe I would purchase a new denso o2 sensor. Also, I can feel the lifter tick pulling timing when it's ticking at its loudest so I need to find an inexpensive way to quiet it down. I'm going to also for fun of it, pull my spare stock FPR and replace it.
 
did you try the lucas oil stabilizer for the lifter tick? and if the lifter are clogged maybe run some sea foam in the oil for 5 min then drain it. ive used seafoam in oil on a 420a that had slight lifter tick (dirty lifters) and it helped
 
did you try the lucas oil stabilizer for the lifter tick? and if the lifter are clogged maybe run some sea foam in the oil for 5 min then drain it. ive used seafoam in oil on a 420a that had slight lifter tick (dirty lifters) and it helped

I'll be picking some Lucas up when I pull it apart this weekend, also good idea on seafoam might have to get that also.

For now, I've put a used denso sensor o2 in there and it seems like it helped ever so slightly but I can't really tell.

Would this kit work for my Manifold to Turbo hot side as well as O2 housing to Turbo hot side?
Fel-pro Turbo Mounting Gasket Set
Part No. ES 72787
 
Last edited:
Ok, so I have a few stripped valve cover bolt threads...great. Anyways, just wondering if this kit might work for repair of them?

Heli-Coil - Metric Thread Repair Kit

Line: HEL | Part # 5546-6
  • Size & Length: M6 x 1 x 9.0mm
  • Coarse
  • Contains: 570-6 Tap, 3747-6 Install Tool & R1084-6 (12) Inserts
  • Prewinder Body Not Included
  • Use 1/4" Drill Bit Not Included
  • Thread Size: M6-1.0
going to be adding some lucas oil stabilizer today just to see if it helps any with ticking.
 
Alright, well this thread is going to stall for a little. I will repost status of performance once I replace those gaskets for the exhaust!
 
So as of now, gaskets are ordered and should be here shortly. The car is pretty much non-driveable with it running so rich, so for the time being I swapped my stock maf sensor with a one that has the lower honey comb removed and the idle screw backed all the way out. It seems like it "bandaided" it to where it's driveable, still that hesitation and full boost but no power around 25% of the time.
 
well it sounds like its heading in the right direction to getting fixed. did you ever swap out the FPR and see if there was any change in driveability?
I have not yet, probably tonight. I pulled the vacuum hose off of the one on the car and there isn't any leaking fuel. Is there actually a way to test the stock fpr or just swap and maybe it helps?
 
well if its sticking close then it might not be regulating fuel pressure correctly (more pressure=more fuel being sprayed out) as far as testing im not to sure, im trying to remember off the top of my head if there was a fuel pressure test port, but I would say easiest way is just to swap parts since its kinda easy to get to
 
here I read this on a forum and this was how he made a tester for a stock fuel system, I believe he just used a regular screw-in type fuel pressure gauge

"That tester would work fine, but using it on the return line will just give you a zero reading. There is no pressure on return side after regulator, you want to test fuel at the fuel-rail inlet side. I have a tester similar to the one you mentioned, I just cut my rubber hose after the filter and inserted the tee fitting to check the pressure. When I was done I used a brass push-lock fitting and 2 hose clamps.

I reccomend using the gauge and fitting b/c its cleaner and whenever engine is running you just pop your hood and look at it.:thumb:"
 
Try moving around the ignition module connector while the car is running. Try taping it while the car is running. Try taping the cas while car is running. Pay attention if it starts to idle differently after each time. Spray some water in the ignition wires to see if you can hear it arcing. Misfires from injectors are not commen but happen. Weak fuel pump can drive you banana. Dead head the pump and check the pressure. Sometimes pressure is there but no valume. But Most of the time it's from ignition system and or controlling part meaning ecu needs to know when to fire and give command to fire. I would also check compression. That could tell you if your engine is healthy and timed correctly.

Clogged exhaust will do some funny things. The car will not have power that's for sure. If really bad it won't ever start. But it does have a specific sound to it. It's like hissing. Drop the down pipe and go for a ride. If it improves then you found your problem. Spin the turbo by hand. See if it spins freely. Check shaft play while you there. You could also have something like gasket stuck in the turbine and blocking the flow.

What I am getting at you need to identify what problem you have. Is it a misfire or something else.
 
Egr is elimanated. Compression is ok for 205k, it's 150 per cylinder. For some reason I'm assuming (no logger) I'm running rich possibly because of exhaust leaks before o2 throwing it off but the gaskets are on order, I swapped out a possible dead o2 looked really weird compared to a used denso I had in the other car sitting in the garage :( LOL still have to grab the fpr off it that car. I guess compensated for "running rich" by adding a hacked maf with no lower honey comb. Since that and the other o2 it has helped quite a bit, but I know it's no fix and more like a bandaid and I'm trying to pinpoint the problem.
 
I'm going to swap the FPR after work tonight to see if that helps. The things I should really be looking at are the FPR, o2 sensor and CTS for fuel releated relaying back the ECU for input? Gaskets should be a few days, might also swap the other stock injectors from the DSM that's sitting.
 
update: different issue now but still has that sputter working on it..

Have to change my t belt and water pump (it's leaking now all of a sudden) on a budget. Not sure how long this car's life has left with 205k so I don't want to spend money on all oem parts for it.

anyone had experience with this: https://www.extremepsi.com/store/product.php?productid=23573
 
The belt kit should be fine, just make sure to get a new tensioner too, unless yours is newer.

Your problem sounds like a boost leak still. Im assuming your boost gauge is tapped into the intake manifold somewhere, so you could either have blow-by or something else is leaking. Try doing section boost leak tests, id start right at the TB/IM and work out from there.

Past that, are you blowing any black smoke or anything? A wideband or logger of some type could help massively right now.
 
The belt kit should be fine, just make sure to get a new tensioner too, unless yours is newer.

Your problem sounds like a boost leak still. Im assuming your boost gauge is tapped into the intake manifold somewhere, so you could either have blow-by or something else is leaking. Try doing section boost leak tests, id start right at the TB/IM and work out from there.

Past that, are you blowing any black smoke or anything? A wideband or logger of some type could help massively right now.

My gauge is tapped by where the stock fpr loops with the intake manifold section. Thanks for the idea! I'm definitely going to try in separate sections.

No, no black smoke under boost. Haven't really driven it as this water pump issue just sprung up.
 
So I went and tested, I'm leaking quite a bit from the release hole in the mbc, a little from the pcv because of a clamp. Main areas also were out of the dipstick and somewhere like underneath the manifold? (I cranked the motor so it's was in different positions) Also, I checked and it seems like the turbo has a little in and out from the shaft.
 
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