1G New to 4 cylinders and fuel Injection

[Meteshjj]

I have always loved DSM cars. My friend had a 91 Laser that was faster than every car we had (except my Cummins). Last week, I decided to buy one. So, for $500 I picked up an untouched, second-owner 1992 Eagle Talon TSi AWD w/ LSD. Aside from the K&N air filter, everything on this car is bone-stock. However, it has been sitting for 4 years.

I've gotten old (Read: unused) cars before, so I did all of the normal stuff to get it going again: Fuel pump, filters all around, cleaner sprayed through all of the hoses, etc. It only had about a gallon of fuel left in the tank, so I diluted it with 11 gallons of premium and some fuel system cleaner. This got the car to fire off of starting fluid, but nothing else.

At this point, I figured the injectors were probably toast, so for $40 I bought some black top 450cc injectors from a friend who has a 2G Eclipse. This got it to run on its own (hooray!). It wouldn't rev up past 4k, though. The same friend suggested that it could be the ECU. Being that he is a Mitsubishi mechanic, I pulled my ECU and noticed rust on the back side. He cleaned off the ECU and replaced the caps with solid-state caps and I put it back in.

Now, the car won't run past 4k unless you add fuel straight to the intake (taking place in the form of carb cleaner). Once you do that, it will rev all the way to redline until it runs out of that fuel. Normally, I'd suspect it being lean, but the tail pipe has a lot of black smoke coming from it. When I pulled the plugs, they were incredibly fouled. Cleaning them does nothing, and they foul again within minutes.

So, my two questions are: will bad fuel do that to a turbo DSM (I've never had problems with it this bad, but those cars were all v8's)? Is it possible the ECU is still dead? Any help would be appreciated. I have a fuel pressure gauge, A/F gauge, and a better boost gauge on the way as we speak, so I'll know more when they get here.

 

[TSi-Rocket]

Wow didn't realize 1g mas were that hard to find I have 3 on the shelf and an extra 2g. Part of my parts hording. I feel maybe I will need all 3 one day or something. If you wanted one I could prob come off one for 35$ and I will test it before the sale. I know how much of a b**ch it is to find parts when you need them so I collect what I can for a rainy day. I'm in the dsm game for the long haul. PM me if interested

 

[darknezz7]

Yeah $700?

See link v3 and socketed ecu go for 450-500 on here quite often.

Listen to gst with psi and everyone here. Health of the engine would be determined by a compression test.

I wouldn't care though, if I found a awd dsm that wasn't beat to complete crap and ran after a few small things for $500 I'd be happy.

 

[RipperXX]

I replaced the ECU CTS. The resistance was not in spec according to the FSM, and it was $5..

Excellent

Both the 1g injectors and the 2g ones I put in are 450cc injectors, so I'm not flowing any more fuel.

Close, but wrong. The dead time between the two will be different, which effects how much fuel is actually injected per open/close cycle.

The 1G MAF is dead. Period. I don't want to spend $200 on another 1G MAF if I know I will eventually be replacing it.

So upgrade, which you have done, good. (sort of)

Right now, I'm aiming for something that will run. Once I'm confident that the car has some life in it, I will spend the money on ECMLink, but I don't feel like dropping $700 on a car that's going to die. I didn't even pay that much for the car.

Define "has some life in it" please. You have to look at the EFI system as a computer in the, garbage in, garbage out sense of things. It has to have the correct information or it at best wont run as well as it could, at worst not at all.

What I've been told is that the 2G signal has a higher frequency that sends more data than the 1G ECU can handle..

Again, sort of. It is a higher resolution sensor, and less restrictive than the 1G unit. But just because the 1G ECU can understand the readings from the 2g sensor, doesn't mean the ECU won't make incorrect adjustments based off of it's data. Think of it as not being calibrated correctly. Once you have ECMLink or a similar solution, you can "inform" the ECU it's getting it's information from a 2G MAF and it will then, in effect be calibrated for the sensor and make correct adjustments based off it's readings.


In closing, these guys and myself have been at this for a good while. Trust us a little more to know what works and doesn't and why.

 

[jimsgsx]

Like i originally said. Just replace the maf and your golden bro. Once again a simple problem snowballed into a giant discussion. Just get a good maf. Your welcome.

 

[Meteshjj]

Dude, where are you shopping for parts, Autozone? $700 for an ECU and $200 for a MAF? I think the last known good MAF I sold here was for like $40 bucks shipped with the airbox included. I've seen ECUs go for a bit over $100. You should be able to get both for under $200.

$200 for a brand new MAF through the parts store I work at. Otherwise, I'm looking at someone's used one which could be DOA for all I know.

$715 is what it would cost me to have the guys at ECMLink socket my non-EProm ECU and set me up with ECMLink.

Step 1, get the proper MAF on the car. You're going to have a horrible time troubleshooting with a 2G MAF on the car. It's a complete waste of time, IMO. Pick up a used known good 1G MAF from somebody in the classifieds, and then do your testing. Quit spending time trying to figure out ways to make the wrong MAF work on the car. As the others have already told you, without a tuning solution, it will never work properly.

I'm not expecting perfect performance. I am trying to get it to run without me having to hold the throttle down. I can't do much in the line of ignition timing without being able to hold RPMs. I can't really do a lot with diagnosing any brake or transmission problems either.

Step 2, inspect your ECU. Most of the time, you can identify damage visually, or by smell. No sense in throwing parts at the car unless you know they are bad. Pop out the ECU, and open the case. After you do that, read through this and inspect: https://www.ecmtuning.com/wiki/ecurepairhome . If you suspect damage, you can send it to the guys at ECMlink for inspection and repair. Typically, a repair is cheaper than a used ECU.

The ECU I have is fine. I've been doing some testing with it, and now that the 2G MAF is even close to correct, the car will run to redline.

Step 3, you should verify the car is mechanically sound before you start troubleshooting all this electrical stuff. You're working backwards, IMO. Check mechanical timing, compression, fuel pressure, spark, etc. These are basic and easy things to check, and can all be done without the car even running. Without these, the car will never run right, whether the MAF and ECU are good or not.

The fuel pressure, compression, and clean spark have all been verified. I did all of that prior to even starting the engine.

Now, on to new stuff.

I have installed permanent fuel pressure, boost, and A/F mixture gauges. Even with the 2G MAF, I'm running around 13.5:1 at idle and 14-15:1 under load. It's running leaner than I'd like, but that seems to be a relatively safe level. I still don't know what it's like at WOT (I have much more to do before that), but it seems like it's okay to run while I deal with the rest of the car.

 

[pauleyman]

How many times do we have to tell you it is not ok.

 

[darknezz7]

Dude thats way too lean under load, thats cruising and idle afr.

 

[Meteshjj]

How many times do we have to tell you it is not ok.

14.7 is stoichiometrically ideal, correct? That would be the best place to run. Under load, it is running in the upper 14's to low 15's. I fail to see where being slightly rich is a problem.

Dude thats way too lean under load, thats cruising and idle afr.

When I say under load, I don't mean with the hammer down. I mean while the engine is engaged to the wheels. That IS what it's like cruising. Under acceleration, it's a little higher than that.

Again, I know that everything should be a little richer, but hanging around 14-15 throughout the RPM range while under load doesn't seem to me like it's running too lean.

 

[pauleyman]

Higher number is lean not rich.

 

[Meteshjj]

Higher number is lean not rich.

Sorry, I meant lean. It was just a long day.

UPDATE:

I bought a known working 1G MAF, and now the car is running rich to the point of barely being able to idle. I don't know if my original MAF was bad now, but I know this one is good, and nothing changed. I changed to O2 sensor (the other one seemed kind of lazy), and there was an improvement to the idle, but the car is still running so rich that I can't get past 2.5k RPMs. Now, the only throttle bodies I have dealt with were diesels, TBI injection, and carburetors, so is there something in there that's supposed to lean the mixture out that is possibly not working? TBI setups have an Idle Air Control valve/solenoid that will adjust the air flow, but I don't see anything quite like that on here.

 

[Chumpaumpalumpa]

We have an Idle speed controller yes. Here read/try this: http://www.dsm.org/how-tos/tttt/tttt3.html
I doubt that's your problem though.
Does the car smoke when you rev it? What AFRs are you seeing now at idle and if you rev and if you keep it at 2.5k? Does it sound like a misfire at all? I left the intercooler piping after the turbo off once and it did something similar.

 

[Meteshjj]

It seems like that system is very different from the ones I'm used to. It doesn't seem like they work the same way, so I doubt it's the problem.

At idle, when it holds at 2.5k under load (while in gear), and when it's at 3.5k in free rev, my gauge is pegged to rich. The needle is buried. When I let off the throttle, it drops down to where the gauge will still read, but only briefly before going back to excessively rich.

EDIT:

I forgot to mention; at anything above idle, a lot of black smoke comes out of the tail pipe.

 

[pauleyman]

Are you sure those are stock injectors? All intercooler piping is hooked up?

 

[pauleyman]

Is this an automatic cat?

 

[Chumpaumpalumpa]

Have you boost leak tested the car? You may find some massive leaks.

 

[Meteshjj]

I checked the numbers on them, and according to everything I've found, they're 450cc injectors, which is what it came with. It originally had blue top injectors, but these are black tops, though, so they might flow more fuel.

The car is a 5-speed manual AWD transmission, and it always has been. I'm the third owner and the previous two kept records on absolutely everything, so I don't think it's been modified.

I haven't gotten a chance to leak test the system, but even at idle (when it's under vacuum) it's running rich. In my experience, vacuum leaks make it run lean, at least with turbo diesels. I'll build a pressure tester this afternoon and see what I can find.

 

[Chumpaumpalumpa]

I checked the numbers on them, and according to everything I've found, they're 450cc injectors, which is what it came with. It originally had blue top injectors, but these are black tops, though, so they might flow more fuel.

The car is a 5-speed manual AWD transmission, and it always has been. I'm the third owner and the previous two kept records on absolutely everything, so I don't think it's been modified.

I haven't gotten a chance to leak test the system, but even at idle (when it's under vacuum) it's running rich. In my experience, vacuum leaks make it run lean, at least with turbo diesels. I'll build a pressure tester this afternoon and see what I can find.

Are your O2 sensors both good? Is the cat good? Are you 100% sure you have no exhaust leaks, especially at the manifold?

 

[Meteshjj]

My upstream O2 is good. I don't know about the downstream. The cat is questionable. It very well could have an exhaust leak. I haven't seen one, but I haven't been looking too hard.

I did find a big boost leak, though. When the PO took the j-pipe off last, he got a little wire bracket stuck between the j-pipe and the turbo, so the gasket wasn't sealing. At all. It was the only place it was leaking from turbo to throttle body. I put that all together, and...

... now it won't start. The temperature dropped by about 25F here, and now it won't even try to fire. Before, sometimes it would take some convincing, but today didn't get warmer than the 50's, and it won't even try to start unless I spray some starting fluid in the intake, and even then, it dies after that's all burnt.

 

[Mauispyder]

Fill out a DSM profile so we can see what's stock and what's not. It more efficient troubleshooting that way.

 

[Meteshjj]

Fill out a DSM profile so we can see what's stock and what's not. It more efficient troubleshooting that way.

The only thing that's not stock right now is the injectors. It has 2G 450cc injectors. Otherwise, it's completely stock.

 

[GST with PSI]

A 2G MAF is not stock...

 

[Chumpaumpalumpa]

A 2G MAF is not stock...

Wait Did you just get appointed wiseman? If so congrats it's about time

 

[pauleyman]

And if you didnt find that leak before it means you havent pressure tested. You need to do a boost leak test.

Read closely, op already changed back to 1g maf.

 

[Meteshjj]

I changed it back to a 1G MAF. It ran like crap. I performed a boost leak test and found the j-pipe problem. Now, there are no leaks. It got cold here, and now it won't start at all.

 

[Meteshjj]

UPDATE:

On the advice of a friend, I checked the throttle position sensor. It was way, way off. I took off the throttle body, gave it a good cleaning, did my best to pressure test it, and adjusted the TPS. Now, it runs pretty great. It doesn't misfire any more, it has 10-12 PSI of boost under load, and it's actually got some power.

Right now, it has trouble carrying itself above 4.5k RPMs under load, but it's not misfiring like it was before. It just doesn't seem to have the power. I'm inclined to blame it on the crappy fuel that's in it. Once I drain that tank and fill it with good fuel, I will report back with the results.