To make a long story short. I let someone borrow it for a couple days. It seemed ok when I got it back. I just moved it on Sat. and everything was ok. Sunday I went out to drive it and it wouldn't stay running. I got it to finally run. I drove hit to work on Monday and could tell it wasn't right. I was on my way home and it shutdown. I got it started but in safe mode (reduced engine power). I was just a mile from home so I drove it there. I pulled the codes. P1870(Tranny slipping) P0102(MAF) and P1514.

I cleared the codes and cleaned the MAF. Got hit started and it ran ok for about a mile before it all started again. I kept it running by keeping my foot on the gas and brake pedal. After about a mile it started running better until I got home.

Here is the interesting part. When you push on the gas pedal the lights dim a little.

Any help or insight would be amazing. I drive it daily to work and it is putting a damper on the family to only have one car.

 

Any help??

 

OK the P1514 code comes up as Throttle body Performance. Basicly this says that what the computer is reading for engine load does not fit with the readings from the throttle body. Your MAF and TPS do not compare well to the RPM and O2 readings. This could be an issue with the MAF, THrottle body itself (as the TPS and servo are one unit the entire TB needs to be replaced if either unit fails). This can also be caused by the ICU if it is sending incorrect RPM readings to the computer (it should be the same as the CKS reading). O2 sensors not reading properly but still in tollerance can also be a factor here.

Having a MAF code could be a failing or failed MAF in which case cleaning does no good. There could also be an intake leak after the MAF which will throw readings all to peices and confuse the nuts out of your PCM. Check for intake leaks. Do you have the factory intake and air box on the car? If so good if not check this over really good to make sure it is not causing any oil to get on the MAF and that it is getting good fresh air comming in. Also check for air leaks at the EGR as fresh air comming into the EGR can throw your metering all to hell as well.

A bad TPS can cause issues with the Trans control as the PCM cannot decide when to shift properly based on incorrect engine load conditions. If the PCM is having a hard time deciding when to shift (in and out of the next gear quickly) then it can also trip a slipping trans code. Again we are looking at the TB for this. A bad trans could cause a TB code to set but it is not as common.

For the lights dimming when you hit the gas could mean your TB servo is using more than the normal ammount of current to operate and or your alternator is dying but not yet dead. I have idle tested alternators and they were fine but just off idle and they were dead. Make sure you load test your alternator at idle and at about 1500-2000 RPM.

Massey

 

Whenever you have lights dimming, pulsing or flickering, you should check your alternator as well -- a couple times I have had pulsating dash lights/headlights and the alternator was on the way out...

 

Document ID# 348426
1999 Chevrolet/Geo Camaro
DTC P1870 Transmission Component Slipping 3.8L




DTC P1870 Range Reference Thumbnail 4L60-E

Range

Gear

Shift Solenoid

TCC Solenoid

TCC PWM Solenoid

2-4 Band

Forward Clutch

3-4 Clutch

Torque Converter Clutch

1-2

2-3

Overdrive

4th

ON

OFF

ON

90% (ON)

Applied

Applied

Applied

Applied

Circuit Description

The powertrain control module (PCM) monitors the difference between engine speed and transmission output speed. In D3 drive range with the TCC engaged, the engine speed should closely match the transmission output speed. In D4 drive range, with the TCC engaged, the TCC slip speed should be -20 to +50 RPM. The table above indicates solenoid states and transmission components that apply, during 4th gear, with the TCC commanded On.

When the PCM detects excessive TCC slip when the TCC should be engaged, then DTC P1870 sets. DTC P1870 is a type B DTC.

Conditions for Running the DTC

No TP sensor DTCs P0122 or P0123.
No VSS assembly DTCs P0502 or P0503.
No TCC solenoid valve DTC P0740.
No 1-2 SS valve DTC P0753.
No 2-3 SS valve DTC P0758.
No 3-2 SS valve assembly DTC P0785.
No TCC PWM solenoid valve DTC P1860.
The engine speed is greater than 450 RPM for 5 seconds.
The engine is not in fuel cutoff.
The vehicle speed is 48-120 km/h (30-75 mph).
The speed ratio is 0.65-0.98 (speed ratio is engine speed divided by transmission output speed).
The engine speed is 1000-3000 RPM.
The engine torque is 40-450 lbs ft.
The gear range is D4.
The commanded gear is not 1st gear
The TP angle is 8-35%.
The TFT is between 20-130°C (68-266°F).
The shift solenoid performance diagnostic counters are zero.
Conditions for Setting the DTC

DTC P1870 sets if the following conditions occur for three TCC cycles.

The TCC is commanded ON for 5 seconds.
The TCC is at maximum duty cycle for 3 seconds.
The TCC slip speed is 200-800 RPM for 7 seconds.

Important

The following actions may occur before the DTC sets.

If the TCC is commanded ON and at maximum duty cycle for 5 seconds, the TP angle is 7-40%, and the transmission slip counter has incremented to either 1 or 2 (out of 3 to increment the fail counter for the current ignition cycle), then the following slip conditions and actions may increment the fail counter for the current ignition cycle: These conditions must occur sequentially.
Condition 1: If the TCC slip speed is 200-800 RPM for 7 seconds, then the PCM commands maximum line pressure and freezes shift adapts from being updated.
Condition 2: If Condition 1 is met and the TCC slip speed is 200-800 RPM for 7 seconds, then the PCM commands the TCC OFF for 1.5 seconds.
Condition 3: If Condition 2 is met and the TCC slip speed is 200-800 RPM for 7 seconds, then the fail counter on the current ignition cycle is incremented.
The above slip conditions and actions may be disregarded if the TCC is commanded OFF at any time as a result of a driving maneuver (sudden acceleration or deceleration).

Action Taken When the DTC Sets

The PCM illuminates the malfunction indicator lamp (MIL) during the second consecutive trip in which the conditions for setting the DTC are met.
The PCM inhibits TCC engagement.
The PCM commands maximum line pressure.
The PCM inhibits 4th gear if the transmission is in hot mode.
The PCM freezes shift adapts from being updated.
The PCM stores DTC P1870 in PCM history during the second consecutive trip in which the conditions for setting the DTC are met.
Conditions for Clearing the MIL/DTC

The PCM turns OFF the MIL during the third consecutive trip in which the diagnostic test runs and passes.
A scan tool clears the DTC from PCM history.
The PCM clears the DTC from PCM history if the vehicle completes 40 warm-up cycles without an emission-related diagnostic fault occurring.
The PCM cancels the DTC default actions when the fault no longer exists and the ignition switch is OFF long enough in order to power down the PCM.
Diagnostic Aids

Internal transmission failures may set DTC P1870.

Test Description

The numbers below refer to the step numbers on the diagnostic table.

This step tests the torque converter for slippage while in a commanded lock-up state.

DTC P1870 Transmission Component Slipping (3.8L, VIN K)

Step

Action

Value(s)

Yes

No

1

Was the Powertrain On-Board Diagnostic (OBD) System Check performed?

--

Go to Step 2

Go to Powertrain On Board Diagnostic (OBD) System Check in Engine Controls

2

Perform the transmission fluid checking procedure. Refer to Transmission Fluid Checking Procedure .

Did you perform the fluid checking procedure?

--

Go to Step 3

Go to Transmission Fluid Checking Procedure

3

Install the Scan Tool .
With the engine OFF, turn the ignition switch to the RUN position.

Important

Before clearing the DTC, use the scan tool in order to record the Freeze Frame and Failure Records. Using the Clear Info function erases the Freeze Frame and Failure Records from the PCM.

Record the DTC Freeze Frame and Failure Records.
Clear the DTC.
Drive the vehicle in 4th gear with the TCC commanded ON.
Is the scan tool TCC Slip Speed within the specified range for 7 seconds?

200-800 RPM

Go to Step 4

Go to Diagnostic Aids

4

Inspect the torque converter clutch (TCC) solenoid valve for the following conditions:
Internal malfunction (such as sediment or damage)
Damaged seals
Inspect the torque converter clutch pulse width modulation (TCC PWM) solenoid valve for the following conditions:
Internal malfunction (such as sediment or damage)
Damaged seals
Did you find a condition?

--

Go to Step 13

Go to Step 5

5

Inspect the 1-2 shift solenoid (SS) valve for the following conditions:
Internal malfunction (such as sediment or damage)
Damaged seals Refer to Shift Solenoid Leak Test .
Inspect the 2-3 SS valve for the following conditions:
Internal malfunction (such as sediment or damage)
Damaged seals Refer to Shift Solenoid Leak Test .
Did you find a condition?

--

Go to Step 13

Go to Step 6

6

Inspect the valve body assembly for a stuck regulator apply valve.

Refer to Unit Repair.

Did you find a condition?

--

Go to Step 13

Go to Step 7

7

Inspect the torque converter assembly for the following conditions:

Stator roller clutch not holding
Internal damage
Did you find a condition?

--

Go to Step 13

Go to Step 8

8

Inspect the oil pump assembly for the following conditions:

Stuck converter clutch valve
Converter clutch valve assembled backwards
Mispositioned converter clutch valve retaining ring
Mispositioned pump to case gasket
Restricted orifice cup plugs
Damaged orifice cup plugs
Over-tightened, or unevenly tightened pump body to cover bolts
Refer to Unit Repair.

Did you find a condition?

--

Go to Step 13

Go to Step 9

9

Inspect the input housing and shaft assembly for the following conditions:

Cut turbine shaft O-ring seal
Damaged turbine shaft O-ring seal
Restricted turbine shaft retainer and ball assembly
Damaged turbine shaft retainer and ball assembly
Refer to Unit Repair.

Did you find a condition?

--

Go to Step 13

Go to Step 10

10

Inspect the 2-4 band assembly for the following conditions:

Worn 2-4 band
Damaged 2-4 band
Mispositioned 2-4 band
Misassembled 2-4 band
The band anchor pin is not engaged.
Restricted apply passages in the 2-4 servo assembly
Blocked apply passages in the 2-4 servo assembly
Nicks or burrs on the servo pin
Nicks or burrs on the pin bore in the case
Damaged fourth servo piston
Misassembled fourth servo piston
Damaged band apply pin
Incorrect band apply pin
Damaged servo bore in the case
Missing piston seals
Cut piston seals
Damaged piston seals
Porosity in the pistons
Porosity in the cover
Porosity in the case
Damaged piston seal grooves
Plugged orifice cup plug
Missing orifice cup plug
Refer to Unit Repair.

Did you find a condition?

--

Go to Step 13

Go to Step 11

11

Inspect the forward clutch assembly for the following conditions:

Worn clutch plates
Porosity in the forward clutch piston
Damaged forward clutch piston
Missing forward clutch piston inner and outer seals
Cut forward clutch piston inner and outer seals
Damaged forward clutch piston inner and outer seals
Missing input housing to forward clutch housing O-ring seal
Cut input housing to forward clutch housing O-ring seal
Damaged input housing to forward clutch housing O-ring seal
Damaged forward clutch housing
Damaged forward clutch housing retainer and ball assembly
Forward clutch housing retainer and ball assembly is not sealing.
Refer to Unit Repair.

Did you find a condition?

--

Go to Step 13

Go to Step 12

12

Inspect the 3-4 clutch assembly for the following conditions:

Worn clutch plates
Porosity in the 3-4 clutch piston
Damaged 3-4 clutch piston
Missing 3-4 clutch inner and outer seals
Cut 3-4 clutch inner and outer seals
Damaged 3-4 clutch inner and outer seals
Damaged 3-4 clutch spring assembly
Damaged 3-4 clutch apply ring
Damaged piston seal grooves
Plugged orifice cup plug
Missing orifice cup plug
Refer to Unit Repair.

Did you find a condition?

--

Go to Step 13

Go to Diagnostic Aids

13

Perform the following procedure in order to verify the repair:

Select DTC.
Select Clear Info.
Operate the vehicle under the following conditions:
Drive the vehicle in D4, with the TCC ON, and a throttle position of 8-35%.
Ensure that the scan tool TCC Slip Speed is -20 to +70 RPM for at least 7 seconds.
Select Specific DTC.
Enter DTC P1870.
Has the test run and passed?

--

System OK

Go to Step 1

Document ID# 348426
1999 Chevrolet/Geo Camaro

 

Thank you all for the information. I have figured out what it is. I unplugged the MAF and cleared the codes. Ran rought but the only code coming up was the MAF. My mother in law has a 3.8L 2001 Impala. I pulled her MAF (Which is new) and ran it in my car. Ran smooth as butter. No flickering, the idle isn't rough, and no codes. So I will chase down a MAF next week. Thank you all once again.

BTW, I did replace the alternator about 3 months ago.

 

This also looks like useful info:


Document ID# 597219
1999 Chevrolet/Geo Camaro
Info - Component Slipping/DTC P1870 - Diagnosis #99-07-30-005 - (Mar 18, 1999)

Table 1: TCC System Symptom Table
Table 2: Internal Transmission Symptom Table
Component Slipping/DTC P1870 - Diagnosis
1996 Buick Roadmaster

1996 Cadillac Fleetwood

1999 Cadillac Escalade

1996-99 Chevrolet Camaro, Corvette

1996-99 Pontiac Firebird

1996-99 Chevrolet and GMC C/K, M/L, S/T, G Models

1996-99 Oldsmobile Bravada

1996-99 Holden Commodore

with Hydra-matic 4L60-E (RPO M30)

Description

Many technicians experience difficulty when diagnosing 1996-1999 4L60-E transmissions with a DTC P1870 (Transmission Component Slipping).

The purpose of this bulletin is to provide assistance for technicians that have already completed the DTC P1870 diagnostic table in the Service Manual. This bulletin will provide a diagnostic strategy for solving DTC P1870 concerns as well as give some of the most common causes for a DTC P1870.

General Information


Important

Chevrolet Camaro, Pontiac Firebird with 3.8L V6 Engine experiencing a slip condition at 70-90 km/h (45-55 mph) when the TCC applies should refer to Corporate Service Bulletin 77-71-70A for calibration re-flash.
1996 Chevrolet and GMC C/K, M/L, S/T, G Models, and 1996 Oldsmobile Bravada with VCM and 4L60-E (RPO M30) with a slip or flare on the 1-2 and/or 2-3 upshift, or no 3rd or 4th gear, or launch shudder should refer to Corporate Service Bulletin 66-71-03A to ensure that a poor internal ground in the VCM does not exist.
A DTC P1870 indicates that a mechanical malfunction exists. If any other DTC's set along with a DTC P1870, then diagnose those first. A DTC P1860 (TCC PWM Solenoid Circuit Electrical) will set if a TCC PWM solenoid circuit failure exists. A DTC P0740 (TCC Enable Solenoid Circuit Electrical) will set if a TCC enable solenoid circuit failure exists.
When attempting to duplicate DTC P1870, it is critical that a normal operating temperature of 82°C (180°F) to 93°C (200°F) be reached. It may be difficult to attain the transmission temperature required to adequately cause the DTC to duplicate. Allow the vehicle to idle to assist in warming the powertrain.
Optimum speed to duplicate the DTC P1870 is between 89 km/h (55 mph) and 107 km/h (63 mph).
Commanding the TCC ON and OFF several times with the Tech II is critical to monitoring slip when sticky valves in the valve body are suspect.
If the customer brought in the vehicle for a temporary harsh 1-2 shift and no driveability concerns are seen during a test drive, then remember that a harsh 1-2 is a result of the PCM commanding maximum line pressure from recognizing a DTC P1870.
The PCM must recognize that a DTC P1870 has set in two consecutive key cycles to illuminate the MIL. If a DTC P1870 is not recognized on a second key cycle, then normal line pressure returns.
Vehicles should be inspected for correct tire size, axle ratio, or calibration.
Diagnostic Approach

Action

Yes

No

Attempt to duplicate DTC P1870.

Did you duplicate DTC P1870?

Go to Slip Check Procedure

Go to TCC System Symptom Table

Slip Check Procedure
This procedure will assist in isolating what area of the transmission is causing your slip, either the TCC system or internal transmission components. After you have isolated the origin of the slip, then utilize the TCC System Symptom Table or the Internal Transmission Symptom Table of this bulletin for most common concerns.

To check for a TCC system concern
TCC slip can occur either hot or cold or in both conditions. First, perform the following test at cold transmission temperatures, then perform the same test at normal operating temperature. Ideal slip from the transmission with the TCC applied is 50 RPM or less under light to normal throttle, no heavy engine load or hard accelerating conditions.

Use the Tech II scan tool to monitor TCC slip while driving the vehicle in 4th gear at steady speed with the TCC commanded ON.
When the TCC is applied or released (release the TCC with brake pedal, not the scan tool - release the TCC by lightly applying the brake pedal while simultaneously maintaining a steady throttle position), the slip speed should drop or rise 150-300 RPM. If the slip speed does not drop, then the DTC P1870 is being caused by the torque converter system.
Action

Yes

No

Did TCC slip speed drop (150-300)?

Continue Slip Check Procedure for an internal trans concern

Go to TCC System Symptom Table

To check for an internal transmission concern
Slip should be checked in every gear to isolate in which gear the slip may be occurring. Drive the vehicle in each forward gear range D1, D2, D3 and D4. Command the TCC ON with the Tech II in each gear and monitor slip speed.


Important

Vehicle speed must be over 11 km/h (7 mph). Some TCC slip is normal when the TCC applies directly after 11 km/h (7 mph) is reached.

If the slip speed remains constant from gear to gear, then the condition is most likely TCC related. Example: Slip speed is higher in second and fourth gear than in third gear. This would lead a technician to a possible slipping band.

Action

Yes

No

Is slip speed equal in all gears?

Go to TCC System Symptom Table

Go to Internal Transmission Symptom Table


Important

These symptom tables are to be used when the following symptoms are associated with a DTC P1870.

TCC System Symptom Table

Symptom

Causes

TCC SLIP (100 RPM SLIP)

Check for bronze bushing material in the pan and filter. If bronze material is present, then the stator bushings (234) and turbine shaft (241) should be replaced (Bronze bushing may turn black with an acrid odor).
The turbine shaft and housing (621) should be replaced if damaged.
In rare instances, it may be necessary to check for an overheated torque converter (24) (Blue and/or distorted converter).
TCC solenoid (66) - Perform leak check.
Converter clutch valve (224) in pump should be checked for 13 mm (0.500 in) of bore travel without binding.
Turbine shaft O-ring seal (618) cut.
Turbine shaft hole not drilled to full depth. This concern can be checked by squirting trans fluid through the turbine shaft hole to check for full flow. This is a low mileage failure.
NO TCC APPLY (300 RPM SLIP)

Converter clutch valve (224) stuck closed (Check for debris in valve bore).
TCC PWM solenoid (396) broken/cracked. Visually inspect solenoid.
TCC solenoid (66). Perform leak test.
Turbine shaft O-ring seal (618) omitted.
TCC SLIP WITH STALL STUMBLE

Converter clutch valve (224) stuck open (TCC is applying).

INTERMITTENT TCC, OK COLD, SLIPS HOT

TCC PWM solenoid (396). Leak test solenoid.
The TCC regulator apply valve (380) and/or converter clutch shift valve (224) may be sticking/side-loading. It is possible there will not be any damage to the valve upon inspection. Transmissions produced after 2/1/98 will have a groove cut into the spring end of the regulator apply valve. This design is to help float the valve in its bore (replace valve body assembly).
Internal Transmission Symptom Table

Symptom

Causes

3RD OR 4TH GEAR SLIP

3-2 downshift solenoid (394) ball seat retention failed. Leak test solenoid. Usually associated with a 3-4 clutch/band worn.
3rd accumulator retainer and ball assembly (40) leaks. Test for proper check ball operation. Usually associated with burned 3-4 clutch.
NO 4TH OR SLIPPING 4TH

Check ball in the wrong location or extra check ball that has dropped behind the spacer plate during trans assembly. The extra check ball can block the 4th apply servo feed.
Clutch orifice cup plug (238) not fully pressed in.
SLIP/FLARE IN ANY GEAR

Pump slide inner spring (207) or outer spring (206) omitted causing a slow slide response.

NO 3RD

Clutch orifice cup plug (238) blown out.

HARSH 1-2 UPSHIFT

4-3 sequence valve (383) stuck in bore by sediment.

NO 2-3 UPSHIFT

2-3 shift valve (368) or 2-3 shuttle valve (369) stuck in bore by sediment.

NO 3-4 UPSHIFT

3-4 shift valve (385) stuck in bore by sediment.

Service Information

Refer to the appropriate Service Manual for replacement procedures.

Warranty Information

Labor Code: Refer to Labor Time Guide for correct labor operation. Please use the closest available labor operation for the diagnosis performed.



GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the information.
WE SUPPORT VOLUNTARY TECHNICIAN CERTIFICATION

Document ID# 597219
1999 Chevrolet/Geo Camaro

 

definitely sounds like a ground or alternator issue for the dimming lights.

 

It is very common with car that have bad idle up and down to have the lights Dim. It is from the engine RPM falling below its designed RPMs. The alternator stops out putting voltage and you run off battery voltage. As soon as the rpms adjust back over 600-700 light brighten up and everything goes back to normal. Since it only down at the extreme low RPMs for a few seconds it does not really hurt anything.

Sound like he found the issue.