IAC on 2.8 multiport

What would be the symptoms of a bad idle air control motor on an '88 Cavalier 2.8 multiport five speed? This car often is difficult to start, sometimes cranking 5 seconds or
more without firing at all, and I've taken to depressing the accelerator slightly to get it to start, which (I think) helps. Occasionally it starts right up after only a second or so, like it used to. Being warmed up or cold doesn't seem to make much difference. Also, lately when I pull up to a stoplight it sometimes will idle down so far it almost dies, then idles back up, then down, etc. It displays no codes. It has, within the last 20k miles, had a new MAP, TPS, and ECM, as well as plugs, wires, & reconditioned heads. Anyway, would the above symptoms be indicative of a bad IAC? Thanks in advance.
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James Goforth wrote:

The bad idle _could_ be related to the IAC but the other symptoms lean more toward a failing fuel pump. Check the fuel pressure. Before replacing the iac, take it off and clean the carbon out of all the ports in the iac and where it attaches. A 9v. battery will make the iac go in or out a bit each time you touch the contacts.
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James Goforth wrote: What would be the symptoms of a bad idle air control motor on an '88 Cavalier 2.8 multiport five speed? This car often is difficult to start, sometimes cranking 5 seconds or more without firing at all, and I've taken to depressing the accelerator slightly to get it to start, which (I think) helps. Occasionally it starts right up after only a second or so, like it used to. Being warmed up or cold doesn't seem to make much difference. Also, lately when I pull up to a stoplight it sometimes will idle down so far it almost dies, then idles back up, then down, etc. It displays no codes. It has, within the last 20k miles, had a new MAP, TPS, and ECM, as well as plugs, wires, & reconditioned heads. Anyway, would the above symptoms be indicative of a bad IAC? Thanks in advance. **************************************** Paul wrote: The bad idle _could_ be related to the IAC but the other symptoms lean more toward a failing fuel pump. Check the fuel pressure. Before replacing the iac, take it off and clean the carbon out of all the ports in the iac and where it attaches. A 9v. battery will make the iac go in or out a bit each time you touch the contacts. ************************************* Switching ign on but engine not running produces fuel pressure right on specs, until after 1 - 2 seconds when the pump kicks off the pressure drops sharply
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