In need of help in Oakland, CA

[tybagg]

So I have been away from this site for a while since my Starion didn't pass SMOG after three attempts and I just parked it. I miss it and need to stop procrastinating and get the damned thing back on the road so I can drive it and stop paying for storage! I was wondering if there are any members in the Bay Area willing to help a brother in need of another set of hands and some Starquest knowledge?

 

I have a SMOG shop in the area that at least is willing to overlook the visual portion of the test but the car is just running really rich. I guess I'd consider the car heavily modded:

 

Completely rebuilt engine with less than a few thousand miles on after the rebuild, Wiseco forged 8.0-1 (if I remember correctly), race-prepped rods, BSE kit (fully balanced) new Marnal NJV head with all new components and Street/Strip cam, '89 ECU, Super 16G turbo, 2.5" exhaust from turbo back with pre-cat eliminated, all aluminum hard pipes, open air filter element... that should be all of the pertinent info.

 

I fear at this point I changed too many things at once to pinpoint what exactly is making it run so rich. The only other symptom of any issue is that the car runs hot occasionally, but I suppose I would attribute that to the deletion of my electric fans when one quit and I went to a clutch fan setup. Otherwise the car seems to run alright, though certainly not dialed in and strong like it should be. No leaks anywhere, either.

 

I had my injectors cleaned and flowed a few years back when I finished the build so I assume they are good. Could use new clips I suppose. In an effort to fix what seemed to be a bad stock FPR I installed a rising rate aftermarket FPR and fuel gauge to dial down the pressure and hopefully cheat the SMOG test. Didn't work and that was my last attempt with it turned down to 35 PSI, I think.

 

I feel sort of lost and not sure what my next step should be, especially with my limited funds for this project. I hope it could be as simple as a TPS reset or at worst a new set of injectors. Hopefully someone can point me in the right direction.

 

Any help would be appreciated and sorry for the long post. Hopefully this is an easy fix so I can get back to driving.

 

Thanks all.

[BOOSTED88tsi]

What mas are you running? and cats? egr hooked up? maybe one weekend we can get together and take a look at it.

[tybagg]

I'm running the original MAS that came on the car when I bought it, not a 1G or anything and the honeycomb is still in place.

 

No pre-cat as I have a 2.5 downpipe with that flex piece built in. The main cat is high flow that came on the second hand 2.5" exhaust I purchased when I lived in SoCal. Not sure of the brand. I'd go and look but the car isn't at my home.

 

My knowledge of the EGR system is limited. Does a Krankvent kit bypass that? I do have that installed as it was recommended to me by a knowledgable Quester I knew in SoCal who used to help me out.

 

I'd be down to work it out anytime if you're willing to help me out. My wrenching buddies are too busy these days to lend a hand and we're only hacks really anyway. My car is conveniently parked right next to a store that sells adult beverages so the beer is on me if you care for any. At least that's one positive.

[mistapickles]

disconnect your battery, disconnect your Idle Speed Control, disconnect your Coolant Temp Sensor then reconnect your battery...if it still runs rich you need a new O2 sensor

[tybagg]

Thanks for that response Pickles, I'll do that this weekend.

 

Speaking of O2 sensors, my exhaust came with an additional O2 sensor and bung already welded on at the bottom of the down pipe. I was told this is an alternative location to hook up a wideband AFR rather than having to splice in to the factory located O2.

 

Is this information correct? If so are there any disadvantages to doing this?

[Metric-man]

disconnect your battery, disconnect your Idle Speed Control, disconnect your Coolant Temp Sensor then reconnect your battery...if it still runs rich you need a new O2 sensor

 

Your engine needs to be up to operating temperature and your o2 sensor warmed up (or heated 2 or 3 wire)

for that to work,

If your engine is cold, once you disconnect your battery, you clear your engines trouble codes and sram.

Your computer still needs to read the CTS or a resistance from you ISC to at least choose a map to use.

If you have you both of those disconnected after you disconnect your battery and your car is cold, your car won't start.

 

 

What I think Mr P is trying to say is it is either your O2 sensor, or your Coolant Temperature Sensor.

 

If after your car warms up, (upper radiator hose is warm) and you turn off the ignition and disconnect the O2 sensor and

if your car still runs normal, it is your O2 sensor that needs replacing ,

because your fuel system is not going into closed loop operation.

 

What temperature rating is the engine coolant thermostat ? 160 ? 180 ? 190 ?

 

Have you inspected the o2 sensor, if your running rich it probably has carbon buildup on the casing,

if you have a coolant leak, even a small one, it could be contaminated.

 

If it is not the answer you need to look for unmetered air entering the system and giving your o2 sensor false readings,

and it could be as close as your exhaust manifold, a crack in the manifold a loose manifold stud...

is the extra bung for the auxiliary wide band up stream (before)

or down stream (after) the stock o2 location on the down pipe ? is the plug for the bung tight ?

 

Do you have your EGT hooked up ? is the gasket still good, or was it reused ? was your throttle body ever rebuilt,

or the gaskets ever replaced ? have you pressure tested the intercooler and intake pipes.

 

Have you pressure tested the cooling system ?

 

Have you checked for ECU trouble codes ?

 

let BOOSTED88tsi help you since he's experienced and near by

[mistapickles]

Thanks for that response Pickles, I'll do that this weekend.

 

Speaking of O2 sensors, my exhaust came with an additional O2 sensor and bung already welded on at the bottom of the down pipe. I was told this is an alternative location to hook up a wideband AFR rather than having to splice in to the factory located O2.

 

Is this information correct? If so are there any disadvantages to doing this?

widebands are typically placed further down the exhaust system, so that is where they go, they don't replace your current O2. They are a system that isn't linked to your car's system.

 

Your car will start without all those sensors connected, mine does every day. With Starquests, if a sensor is unplugged, the computer acts as if the sensor is plugged in and at perfect operating temperature. I think what Metric is trying to say is your car will be a little more difficult to start if it's cold outside, and that would be because the computer thinks the car is already warm and has fuel adjusted for that. If it is really cold you will have to sit in your car hold the idle at 1500 until it is actually warmed up, but then it will run normally. As far as fuel maps go, our cars don't "choose" fuel maps, they "make" fuel maps based on how you drive and it will make a fuel map without the ISC and CTS just fine, because, once again, it thinks everything is at perfect operating temperature. Once the battery is unplugged, just like the trouble codes, your fuel maps are cleared and new ones get made when you get going again, usually in about 50 miles your fuel maps are set. Never disconnect a sensor, O2 or otherwise, with the battery connected.

 

Try doing the simple things first, before getting into the brain surgery type stuff, most of the time its the simple things.

[Metric-man]

widebands are typically placed further down the exhaust system, so that is where they go, they don't replace your current O2. They are a system that isn't linked to your car's system.

 

Your car will start without all those sensors connected, mine does every day. With Starquests, if a sensor is unplugged, the computer acts as if the sensor is plugged in and at perfect operating temperature. I think what Metric is trying to say is your car will be a little more difficult to start if it's cold outside, and that would be because the computer thinks the car is already warm and has fuel adjusted for that. If it is really cold you will have to sit in your car hold the idle at 1500 until it is actually warmed up, but then it will run normally. As far as fuel maps go, our cars don't "choose" fuel maps, they "make" fuel maps based on how you drive and it will make a fuel map without the ISC and CTS just fine, because, once again, it thinks everything is at perfect operating temperature. Once the battery is unplugged, just like the trouble codes, your fuel maps are cleared and new ones get made when you get going again, usually in about 50 miles your fuel maps are set. Never disconnect a sensor, O2 or otherwise, with the battery connected.

 

Try doing the simple things first, before getting into the brain surgery type stuff, most of the time its the simple things.

The Circa 1980's computer the Starion/Conquest's use is quite simple, and it is barely more significant than an electronic feedback carburetors computer

The Starion /Conquest's ECU was pre-programed from the factory, that is why the MAS, fuel injectors , and ECU's were mated to their respective corresponding production year for a vehicle.

 

The adaptive Random Access Memory (RAM) a Starion/Conquest ECU stores is actually erased after the ECU or the vehicles battery is unplugged

so it that sense it is actually Static RAM and it stores memory for later calculations which is different from later automotive computers that actually write fuel maps.

 

(SRAM)...is still volatile in the conventional sense that data is eventually lost when the memory is not powered.

http://en.wikipedia.org/wiki/Static_random_access_memory

 

Another example of the Early ECU's inability to be programed, but instead were transplanted with a "chip"

http://en.wikipedia.org/wiki/Chip_tuning

This was done with early engine computers in the 1980s and 1990s. Today, the term chip tuning can be misleading, as people will often use it to describe ECU tuning that does not involve swapping the chip. Modern ECUs can be tuned by simply updating their software through a standard interface, such as OBDII. This procedure is commonly referred to as engine or ECU tuning. ECUs are a relatively recent addition to the automobile, having first appeared in the late 1970s.

 

 

http://i1083.photobucket.com/albums/j382/Starion_Cult/ECI%20TURBO%2083-86/TBIFuelTurbocharging032.jpg?t=1299315263

Edited March 5, 2011 by Metric-man

[mistapickles]

Try doing the simple things first, before getting into the brain surgery type stuff, most of the time its the simple things.

yeah, the computer only has a few ways to determine how much fuel to give, the MAF, the CTS, the ISC and the O2. Since you can't unplug the MAF on cars newer than 87, you can unplug everything else and see what happens.

 

I don't know what all that stuff Metric posted means and two of the quotes I have know idea where they came from, but I did sleep at a Holiday Inn Express the other night...seriously though, once my car ran so rich it dribbled raw gas out the exhaust, and it turned out to be both my ISC and CTS. It may work, it may not, let me know either way because I might eventually have the same thing to fix on my car.

Edited March 5, 2011 by mistapickles

[Metric-man]

yeah, the computer only has a few ways to determine how much fuel to give, the MAF, the CTS, the ISC and the O2. Since you can't unplug the MAF on cars newer than 87, you can unplug everything else and see what happens.

 

I don't know what all that stuff Metric posted means and two of the quotes I have know idea where they came from, but I did sleep at a Holiday Inn Express the other night...seriously though, once my car ran so rich it dribbled raw gas out the exhaust, and it turned out to be both my ISC and CTS. It may work, it may not, let me know either way because I might eventually have the same thing to fix on my car.

The quotes are with the links attached.

There have been 87's that can run with out the MAS plugged in...

but all that is from is the fail-safe (limp home or Holiday Inn) mode the engineers designed in

 

Pickels not saying your help isn't relevant,

but since our cars have a computer controlled system it makes more sense to use it diagnostic ability

as a tool to help determine the problem, (more economical with time and money)

[tybagg]

Thanks to everyone for their help! Sounds as if I have a good checklist of things to diagnose and that's much more than I could say before. I'll make a list starting with simple and moving towards the more complicated.

 

Metric mentioned how the MAS, ECU and injectors are all year specific when working properly. Could the fact that I'm using an '89 ECU with a supposed '87 MAS be an issue?

 

I also plan to change my thermostat and plugs after reading a number of other threads on here, too. I don't believe I have the correct parts installed. My thermostat may be stuck open/closed as it is with some of the overheating issues I've had in the past so I might as well.

 

So, Boosted88tsi when is your next available weekend day? Time to get my beloved POS on the road!

[Metric-man]

Thanks to everyone for their help! Sounds as if I have a good checklist of things to diagnose and that's much more than I could say before. I'll make a list starting with simple and moving towards the more complicated.

 

Metric mentioned how the MAS, ECU and injectors are all year specific when working properly. Could the fact that I'm using an '89 ECU with a supposed '87 MAS be an issue?

 

I also plan to change my thermostat and plugs after reading a number of other threads on here, too. I don't believe I have the correct parts installed. My thermostat may be stuck open/closed as it is with some of the overheating issues I've had in the past so I might as well.

 

So, Boosted88tsi when is your next available weekend day? Time to get my beloved POS on the road!

 

The most changes occurred between 85 and 86 with the atmospheric pressure sensors

an 87 MAS probably wouldn't be an issue.

I believe there are more issues using a hacked MAS than the mismatched ones.

the honeycomb inserts are there to induce laminar air flow

when they are removed in the premise of opening them up for more air flow,

it creates more turbulence and gives the sensors false readings

 

Thermostats unless they are the failsafe type (usually) stick closed,

an you can usually tell by the upper radiator hose collapsing after warm up.

 

A good set of NGK's that have the standard electrode not iridium or platinum,

at-least until you get everything running correctly,

and then only if you have a specific purpose on your agenda are the others suitable.

 

If you do disconnect the battery to clear the ECU's memory, do so for about 5 minutes to allow for all electrical current to be discharged,

another method is to use the negative battery clamp after it is removed from the battery post,

and to ground it to the chassis of the vehicle, to help drain any residual current.

 

Armed with basic automotive knowledge, a good electrical multi-meter,

and the proper documentation from the (Chapter group 14 fuel system) in the Factory Service Manual.

(or supplement to) you should be able to get your car running correctly.

 

If you have access to obtain a mechanic's stethoscope to listen to actuators an injectors while the car is running,

it will help you to determine if they are working correctly or acting abnormally.

Edited March 7, 2011 by Metric-man

[The Rabbit1]

Thermostats unless they are the failsafe type stick closed,

an you can usually tell by the upper radiator hose collapsing after warm up.

I just pulled a frozen, wide open thermostat from my motor a few months ago. They can get stuck open.

[Metric-man]

I just pulled a frozen, wide open thermostat from my motor a few months ago. They can get stuck open.

Your right, they can have defects or I suppose be broken from frozen water expansion.

but from tybagg's description and his concern of an overheating problem, it could be closed.

 

Stuck open or not having one installed would cause your car to run cold and possibly not go into closed loop mode..such as having the incorrectly rated thermostat would case your car's CTS to compensate for the temperature difference by controlling the fuel ratio through the open loop mode.

 

On pre 87's (I'm not sure of after 87)

You can by pass most of the TPS functions or if you have a bad TPS by installing the TPS in reverse and have the lever installed for it at 12 o'clock, by tightening the throttle cable, this causes the ISC to act as a throttle plate on a standard carburetor engine and you can adjust idle as you would with a carb.

Edited March 7, 2011 by Metric-man