2.2 turbo EFI, cold-start problem; open/close loop? suggestions?

92 Spirit R/T.

hard start below 40(F) outdoor temps, cold engine. (3-4 hours from last start).

will run for a few seconds, then quit. After repeated attempts it will eventually stay running, albeit, very rough, and w/ exhaust backfire.

Once running for 2 1/2 minutes (almost exactly), regardless of how cold (eg -10 below), it transforms itself, and runs absolutely smooth. very repeatable;

ODB-II shows an accurate temperature.

Almost as though the EFI is transitioning from a closed/open loop program (or vice-versa. I forget if "open" implies, "fixed, no outside sensor inputs", if "closed" does...).

changing SBEC's made no difference. (yeah, that's what the local dealer suggested, and 92 2.2/turbo SBEC's are as rare as chicken teeth ...)

during the initial 2.5 minute back-fire in the exhaust, the exhaust looks/smells way rich; but I've not a good idea how to figure what should be considered "too rich" for a cold motor.

based on experience w/ other EFI motors, I'm tempted to suspect a 5th injector stuck open during the initial 2.5 minutes (does a 2.2/Turbo EFI even have a 5th injector, or something similar?)

Using the Block heater is one work-around (starts like a charm when warm), but that's of no use, when the car is somewhere I cannot plug in.

any Ideas, Suggestions much appreciated.

Reply to
JBloggs
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That car is a lot of fun to drive...not such fun to keep running. They are essentially "production prototypes", and parts can be fearfully expensive. I drove a '91.

Some initial thoughts:

Which exact spark plugs are you running in it?

Have you carefully checked the MAP sensor line for accumulated water and for cracks?

How long since you replaced the O2 sensor *and inspected the O2 sensor wires* where they run below the air cleaner bracket? These wires are easily cooked; they're directly above the exhaust manifold. And, when you replaced the O2 sensor, what brand of replacement did you use?

OK, so it runs poorly below a certain engine coolant temperature, and/or below a certain air charge temperature, and/or there's a problem with the O2 sensor/wiring, and/or the camshaft and/or crankshaft position sensor(s) is/are failing.

OBD. How did you check this?

When you first start up, it's in open-loop. When it warms up, it's in closed-loop.

The SBEC scarcely ever causes problems.

If it smells way rich, it's "too rich".

No 5th (cold start) injector on this system.

Systematic diagnosis. Let's have some answers to the questions above and then we'll go from there.

DS

Reply to
Daniel J. Stern
02 sensor not effected by the cold start, its in open loop, No 5th injector, Assuming that the coolant temp is reading properly along with the otehr sensors i would check the the basic timing and fuel contamination in the vaccum system, if the pressure regulator ruputres it will cause major problems, there is also a TSB out for a complaint such as this. SUBJECT: Long Crank Time/Rough Idle/Tip-In Sag Or Hesitation When Cold DATE: Sep. 21, 1992 THIS BULLETIN SUPERSEDES TECHNICAL SERVICE BULLETIN 18-13-92 WHICH SHOULD BE REMOVED FROM YOUR FILES. ALL REVISIONS ARE HIGHLIGHTED IN RED AND WITH **ASTERISKS**.

NOTE: THIS BULLETIN APPLIES TO VEHICLES EQUIPPED WITH A 2.2L OR 2.5L TBI ENGINE.

SYMPTOM/CONDITION: In cold ambient temperatures (below 35°F or 2°C), vehicles equipped with 4 cylinder TBI engines may exhibit one or more of the following conditions during initial start up:

a.. long crank times b.. rough idle (for 2-3 minutes after starting vehicle) c.. slight sag or hesitation on tip in from idle (for 2-3 minutes after starting vehicle) These symptoms may be caused by poor fuel distribution within the intake manifold, when the engine is cold.

DIAGNOSIS: Verify the customer complaint by cold starting the vehicle in conditions that are as close as possible to those described in under the Symptom/Condition heading (ambient temperature, soak time, etc.). Once the complaint has been verified, use the DRB II (Scan Tool) and the appropriate diagnostic procedures manual to verify that all of the vehicle engine systems are functioning properly (no fault codes [diagnostic trouble codes] are present). If no trouble codes are present inspect the intake manifold for a raised "X" cast into the number 1 runner. The "X" is located under the letter "F" in the words "FIRING ORDER" on the top of the number 1 intake manifold runner as illustrated. Intake manifolds that DO NOT have a "X" should be replaced using the following procedure. ( See Illustration)

PARTS REQUIRED: Quantity Description Part No.

1

Intake Manifold Assembly

Non EGR Equipped **4667173**

EGR Equipped **4667172**

1

Intake And Exhaust Manifold Gasket 4240096

Reply to
maxpower

...except that if the O2 sensor heater wire is shorted to the O2 sensor sense wires, it can cause exactly the symptoms the original poster mentions. Remember, the O2 sensor heater wire is hot during open loop!

Pay closer attention to the car the OP is working on. There is no basic timing to check; the 2.2T3 uses DIS.

Pay closer attention to the symptoms the OP mentions; ruptured fuel pressure regulators do not magically unrupture after 2-1/2 minutes of runtime.

Pay closer attention to the car the OP is working on. It is a 2.2T3, not a

2.2 or 2.5 litre TBI engine.
Reply to
Daniel J. Stern

Reply to
maxpower

Reply to
maxpower

Try again, Max. Not only does he state "turbo" right in the subject line

-- which means 4 injectors, since all of CHrysler's 2.2 Turbo setups have had multipoint -- but he states 1992 Spirit R/T. That means 2.2 Turbo III, which not only means 4 injectors, but also DIS.

Read harder next time.

Sorry, no. Looks like you need to go back to your FSMs. The Turbo III engine *does not* have a distributor in it. There was a 2.2 turbo 16v engine that did have a distributor in it; it was the one in the Chrysler's TC by Maserati, but since the OP stated "1992 Spirit R/T", we know that's not what he's got.

Reply to
Daniel J. Stern

me: "eh? shorted O2 sensor heater wires?.. !!... hmmm."

clomp, clomp, clomp, slam. (dnstairs to the garage...) tinker about, clink, $@#$!, clink. yank! (sound of disconnected O2 wire).

let's see: OBD II, 34 degreess. (coolant/air-charge...) Click? (Ignition...) Vroooomm. Puuuurrrrr ...

WTF ?!

now here, i was looking at the ground straps, DIS/coil-thingies, cam sensor, this/that/what-else ...

Dan, good catch! ...when'd you run across this one? Maybe there's a good story (lesson...) here.

funny thing is, the o2 wires look reasonable, not KFC crispy like some I've seen.

Reply to
JBloggs

Autumn 1998. I pulled in from getting groceries, shut down, went in and put the groceries away. Ten minutes later, went to use the car again...crank, but no fuel pump, no "Check Engine" codes, no spark, no nothin'. The O2S wires (all four of them) had fallen out of their retainer clips on the underside of the air cleaner baseplate heat shield and onto the exhaust manifold, still hot from the grocery trip, and the insulation got vaporised.

As soon as I hit the ignition, the direct short to ground in the O2S heater and sense circuits took out two fuselinks -- Zap, no power to the SBEC, no power to the ASD, no power to the fuel pump or ignition.

I replaced the fuselinks in an unauthorized but effective manner, then repaired the O2S harness using 650C-tolerant wire (robbed from a discarded kitchen oven!), rerouting the new wires *over* the air cleaner baseplate, and the car started right up.

Check them very closely. The fault could be within the O2 sensor itself (heater element internally shorted to ground) -- especially if somebody installed a Bosch unit (junk-junk-junk...always use NTK, Echlin, BlueStreak or Mopar, but never Bosch.)

Fix the problem soon or you'll lunch your catalytic converter, just like my own R/T did the last time I was dumb enough to use Chumpion spark plugs.

DS

225 at torque dot net
Reply to
Daniel J. Stern

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